Electroencephalographic responses and subjective evaluation on unpleasantness induced by sanitary napkins

Correlation of unpleasantness and electroencephalography (EEG)-based responses induced by persistent mechanical/dry stimulation and acute wet stimulation via wearing sanitary napkins (SN) was investigated in the present study. Mesh and nonwoven SN were employed, and the effects were studied during the follicular and menstrual phases. The mesh SN characteristically displayed a higher textural surface-roughness. The results in the follicular phase revealed no change in EEG responses to nonwoven SN-induced persistent mechanical stimulation, while the same dry stimulus induced significant increases in alpha2 and beta activities in the bilateral frontal areas accompanied by markedly exacerbated unpleasantness with mesh compared with nonwoven SN. The present result with SN application confirms the previous finding that unpleasantness is well correlated with EEG responses of bilateral frontal areas. Interestingly, although the alpha2 activities were enhanced more with mesh than nonwoven SN during the menstrual phase, unpleasantness between the two textural materials was not different. Moreover, it is suggested that acute unpleasantness induced by wet stimulation is related with elevated EEG responses in the left hemisphere. These data suggest that subjective evaluation of effects of physical stimulation on the human body may not be adequately reliable, and objective assessment of physiological activities with EEG is warranted.     

Features of cardiovascular functioning during different phases of the menstrual cycle

The purpose of the present study was to determine whether there is a menstrual cycle effect on heart rate, blood pressure and heart rate variability. 10 healthy regularly cycling females (age 19-23 years) were studied during the follicular phase and luteal phase over two month. We found significant changes in heart rate, AMo and stress index during the menstrual cycle with a minimum in the follicular phase and maximum in the luteal phase. The HF and LF components decreased more during the luteal phase than during the follicular phase (p < 0.05), whereas a tendency for increase LF/HF was observed in the luteal phase. In the follicular phase SDNN, pNN50, Mo, MxDMn were significantly higher than in the luteal phase. Furthermore, the VIK was higher in the luteal phase compared to the follicular phase (p = 0.003). Blood pressure did not show any significant change during both these phases of the menstrual cycle. These findings indicate that sympathetic nervous activity in the luteal phase is greater than in the follicular phase, whereas parasympathetic nervous activity is predominant in the follicular phase. A difference of the balance of ovarian hormones may be responsible for these changes of autonomic functions during the menstrual cycle.     

Specific physiological responses in women with severe primary dysmenorrhea during the menstrual cycle

This study examined the specific physiological responses of women with primary dysmenorrhea during the severely painful menstrual (days 1-2 of menstruation) and the non-painful follicular phases (days 5-8 after the onset of menstruation). Subjects consisted of 10 severe primary dysmenorrheic (Group P) and 10 non-dysmenorrheic women (Group C) with regular menstrual cycles. However, only 9 out of 10 and 8 out of 10 subjects of Groups P and C participated during the follicular phase. Physiological measures were taken in a resting state for 60 min. In the menstrual phase, the pain ratings and secretory immunoglobulin A (s-IgA) concentrations of Group P were significantly higher than those of Group C, with relatively significant decreases in the leg-skin temperature in the former as well. In addition, the systolic (SBP) and diastolic blood pressure (DBP) at 45 min after rest in Group P were significantly higher than those found in Group C. These reactions strongly suggest activation of the sympathetic-adrenal-medullary axis (SAM axis) by painful stress. Furthermore, the low-frequency (LF) component of the SBP variability (SBPV) was significantly higher in Group P than Group C, even during the follicular phase. These findings imply that Group P may well have elevated activities of the SAM axis throughout the whole menstrual cycle. As such, it suggests that dysmenorrheic women may be affected by certain stressors other than pain per se and pain-derived emotions throughout the whole menstrual cycle. The findings also indicate that women with dysmenorrhea have more sensitive responses to the SAM system than non-dysmenorrheic women during stress. Moreover, the high-frequency (HF) component of heart rate variability (HRV), or the index for the vagus nerve activity, displayed a consistently higher value in Group P than C. It is postulated that the human body may have responded to pain in an attempt to maintain the homeostatic state by enhancing vagus nerve activity.     

Women's genital sexual arousal to oral versus penetrative heterosexual sex varies with menstrual cycle phase at first exposure

Reproductive-aged women show increased interest in sexual activity during the fertile phase of the menstrual cycle that can motivate sexual behavior and thereby increase the likelihood of conception. We examined whether women demonstrated greater sexual responses (subjective and genital sexual arousal) to penetrative versus oral sexual activities during the fertile versus non-fertile phases of their cycles, and whether women's arousal responses were influenced by the phase during which they were first exposed to these sexual stimuli (e.g., Slob et al., 1991; Wallen and Rupp, 2010). Twenty-two androphilic women completed two identical sexual arousal assessments in which genital responses were measured with a vaginal photoplethysmograph and their feelings of sexual arousal were recorded. Women viewed an array of 90 s films varying by couple type (female–female, male–male, female–male) and sexual activity type (oral or penetrative), during the fertile (follicular) and non-fertile (luteal) phases of their menstrual cycle, with the order of cycle phase at the first testing session counter-balanced. Women tested first in the fertile phase showed significantly greater genital arousal to female–male penetrative versus oral sex in both testing sessions, whereas self-reports of sexual arousal were not affected by cycle phase or testing order. These results contribute to a growing body of research suggesting that fertility status at first exposure to sexual stimuli has a significant effect on subsequent sexual responses to sexual stimuli, and that this effect may differ for subjective versus genital sexual arousal.     

Influence of menstrual cycle on baroreflex control of heart rate: comparison with male volunteers

This study was designed to determine baroreflex control of heart rate (HR) to hypotensive and hypertensive stimuli during the early follicular (EF), preovulation (PreOV), and midluteal (ML) phases of the menstrual cycle and to test the hypothesis that cardiovagal reflex responses to hypertensive stimuli would be altered depending on the plasma estradiol levels in healthy women. In addition, these results were compared with those of male volunteers. Fifteen healthy women with regular menstrual cycles and thirteen male volunteers were recruited. Cardiovagal baroreflex sensitivity was defined as the slope of the linear portion relating R-R interval and systolic blood pressure triggered by bolus injections of nitroprusside and phenylephrine, from the overshoot phase of the Valsalva maneuver, and during spontaneous fluctuations. Three measurements were averaged in each test as a representative at each phase, and the order of phases was counterbalanced. Baroreflex sensitivities by the phenylephrine pressor test and Valsalva maneuver during the PreOV phase were significantly greater than those during the EF and ML phases but were similar to those of men. Depressor test sensitivities by nitroprusside and down-sequence spontaneous cardiac baroreflex sensitivity during the EF phase were significantly greater than those of the ML phase and of men. Significant correlations were observed between plasma estradiol concentrations and baroreflex sensitivities assessed by phenylephrine and the Valsalva maneuver. Our results indicate that baroreflex control of HR is altered during the regular menstrual cycle, and estradiol appears to exert cardiovagal modulation in healthy women.     

Menstrual cycle-related changes in plasma oxytocin are relevant to normal sexual function in healthy women

Circulating levels of the neuro-hypophysial nonapeptide oxytocin increase during sexual arousal and orgasm in both men and women. A few studies have evaluated the effect of the menstrual cycle on plasma oxytocin in normally cycling, sexually active, healthy fertile women using or not using contraceptive pills. In 20 ovulating women and 10 women taking an oral contraceptive (group 1 and group 2, respectively), sexual function, hormonal profile, and plasma oxytocin (OT) were evaluated throughout the menstrual cycle. In group 1, plasma OT was significantly lower during the luteal phase in comparison with both the follicular and ovulatory phases. Plasma oxytocin was significantly correlated with the lubrication domain of the Female Sexual Function Index (FSFI) during the luteal phase and showed a trend towards statistical significance during the follicular phase. In group 2, plasma OT did not show any significant fluctuation throughout the menstrual cycle, even though a significant correlation was evident with both the arousal and the lubrication domain of the FSFI during the assumption of the contraceptive pill. These findings suggest that plasma OT fluctuates throughout the menstrual cycle in normally cycling healthy fertile women with adequate sexual activity but not taking any oral contraceptive pill. Moreover, plasma OT levels significantly relates to the genital lubrication in both women taking and not taking oral contraceptive pill apparently confirming its role in peripheral activation of sexual function.     

Growth hormone secretion after baclofen administration in different phases of the menstrual cycle in healthy women

AIM: The aim of this study was to investigate the effect of baclofen administration on growth hormone (GH) secretion during different phases of the menstrual cycle. METHODS: Twelve healthy women (33.6 +/- (SD) 2.8 years; range 23-40 years) with regular menstrual cycles were enrolled. The phases of the menstrual cycle were determined using transvaginal ultrasonography (TV-US) and detecting hormonal serum levels. Plasma GH levels were evaluated during the early follicular, periovulatory and luteal phases of the cycle before and after the baclofen challenge test. RESULTS: After acute baclofen administration, GH levels increased significantly (p < 0.001) compared to basal values during the periovulatory and luteal phases, while no significant variation was detected during the early follicular phase. In addition, plasma GH levels resulted significantly (p < 0.001) higher during the luteal phase than during the periovulatory phase. CONCLUSION: Acute baclofen administration induces a significant increase in plasma GH levels in healthy females during the periovulatory and luteal phases, but not during the early follicular phase. These data suggest a modulator role of plasma sex steroids levels on GH release induced by baclofen.     

Cardiovascular reactivity to mental stress: relationship with menstrual cycle and gender

The purpose of the present study was to determine the fluctuation in cardiovascular reactivity to mental stress during the menstrual cycle by comparing heart rate variability (HRV), and other physiological and psychological data in females with those in males. Cardiovascular reactivity to two mental tasks was measured in 14 females during the follicular and luteal phase of menstruation over two menstrual cycles. The same tasks were subsequently given to a matched pair of males (N=14), at the same intervals as their corresponding females. Heart rate, blood pressure and HRV were used as indices of cardiovascular reactivity. Subjective mental workload was measured at the end of each task. Power spectral analysis of HRV showed that the high frequency (HF) component in HRV decreased more during the luteal phase than the follicular phase. The low frequency (LF) component in HRV and the LF/HF ratio in the luteal phase were significantly higher than that in the follicular phase. The LF component and the LF/HF ratio were significantly lower in females than in males; conversely, the HF component was significantly higher in females than in males. Neither significant effects of menstrual cycle, gender and mental stress nor any significant interactions were found for mental workload. These findings indicate that sympathetic nervous activity in the luteal phase is significantly greater than in the follicular phase whereas parasympathetic nervous activity is predominant in the follicular phase. The results also suggest that predominance of sympathetic nervous activity in males compared with a dominant parasympathetic nervous activity in females.     

Influence of menstrual cycle and oral contraceptives on tolerance to uncompensable heat stress

In this study we examined the influence of menstrual cycle phase and oral contraceptive use on thermoregulation and tolerance during uncompensable heat stress. Eighteen women (18-35 years), who differed only with respect to oral contraceptive use (n = 9) or non-use (n = 9), performed light intermittent exercise at 40 degrees C and 30% relative humidity while wearing nuclear, biological and chemical protective clothing. Their responses were compared during the early follicular (EF, days 2-5) and mid-luteal (ML, days 19-22) phases of the menstrual cycle. Since oral contraceptives are presumed to inhibit ovulation, a quasi-early follicular (q-EF) and quasi-mid-luteal (q-ML) phase was assumed for the users. Estradiol and progesterone measurements verified that all subjects were tested during the desired phases of the menstrual cycle. Results demonstrated that rectal temperature (Tre) was elevated in ML compared with EF among the non-users at the beginning and throughout the heat-stress trial. For the users, Tre was higher in q-ML compared with q-EF at the beginning, and for 75 min of the heat-stress exposure. Tolerance times were significantly longer during EF [128.1 (13.4) min, mean (SD)] compared with ML [107.4 (8.6) min] for the nonusers, indicating that these women are at a thermoregulatory advantage during the EF phase of their menstrual cycle. For the users, tolerance times were similar in both the q-EF [113.0 (5.8) min] and q-ML [116.8 (11.2) min] phases and did not differ from those of the non-users. It was concluded that oral contraceptive use had little or no influence on tolerance to uncompensable heat stress, whereas tolerance was increased during EF for non-users of oral contraceptives.     

Effects of the menstrual cycle on auditory event-related potentials

Gonadal steroids (estradiol and progesterone) can alter neuronal functioning, but electrophysiological evidence in women is still sparse. Therefore, the present study investigated event-related potentials (ERPs) to neutral stimuli over the course of the menstrual cycle. In addition, associations between ERPs and salivary estradiol and progesterone concentrations were investigated. Eighteen young healthy women were tested at three different phases of their menstrual cycle (menses, and follicular and luteal phases). ERPs (i.e., the N1 and P2 components, reflecting cortical arousal and the orienting response, the N2, P3, and the Slow Wave (SW), reflecting controlled processing) were measured using two different paradigms. In the luteal phase, early ERPs reflecting the cortical arousal response were diminished in the first stimulus block indicating an attenuated orienting response. These changes were significantly correlated with estradiol as well as progesterone levels. As to the later ERP components, the N2 latency was shorter during menses compared to the other two phases. No menstrual cycle-associated changes were apparent in other late ERP components. In sum, this study documents changes in auditory ERPs across the menstrual cycle with the most prominent changes occurring during the luteal phase. Future ERP studies therefore need to be more attentive to the issue of menstrual phase when studying female subjects or female patients.     

Effect of menstrual cycle phase on the ventilatory response to rising body temperature during exercise

To examine the effect of menstrual cycle on the ventilatory sensitivity to rising body temperature, ten healthy women exercised for ~60 min on a cycle ergometer at 50% of peak oxygen uptake during the follicular and luteal phases of their cycle. Esophageal temperature, mean skin temperature, mean body temperature, minute ventilation, and tidal volume were all significantly higher at baseline and during exercise in the luteal phase than the follicular phase. On the other hand, end-tidal partial pressure of carbon dioxide was significantly lower during exercise in the luteal phase than the follicular phase. Plotting ventilatory parameters against esophageal temperature revealed there to be no significant menstrual cycle-related differences in the slopes or intercepts of the regression lines, although minute ventilation and tidal volume did significantly differ during exercise with mild hyperthermia. To evaluate the cutaneous vasodilatory response, relative laser-Doppler flowmetry values were plotted against mean body temperature, which revealed that the mean body temperature threshold for cutaneous vasodilation was significantly higher in the luteal phase than the follicular phase, but there were no significant differences in the sensitivity or peak values. These results suggest that the menstrual cycle phase influences the cutaneous vasodilatory response during exercise and the ventilatory response at rest and during exercise with mild hyperthermia, but it does not influence ventilatory responses during exercise with moderate hyperthermia.     

Menstrual status and plasma vasopressin, renin activity, and aldosterone exercise responses

The effects of menstrual cycle phase (early follicular vs. midluteal) and menstrual status (eumenorrhea vs. amenorrhea) on plasma arginine vasopressin (AVP), renin activity (PRA), and aldosterone (ALDO) were studied before and after 40 min of submaximal running (80% maximal O2 uptake). Eumenorrheic runners were studied in the early follicular and midluteal phases determined by urinary luteinizing hormone and progesterone and plasma estradiol and progesterone assays; amenorrheic runners were studied once. Menstrual phase was associated with no significant differences in preexercise plasma AVP or PRA, but ALDO levels were significantly higher during the midluteal phase than the early follicular phase. Plasma AVP and PRA were significantly elevated at 4 min after the 40-min run in the eumenorrheic runners during both menstrual phases and returned to preexercise levels by 40 min after exercise. Plasma ALDO responses at 4 and 40 min after exercise were higher in the midluteal phase than the early follicular phase. Menstrual status was associated with no significant differences in preexercise AVP or PRA; however, ALDO levels were significantly higher in the amenorrheic runners. After exercise, responses in the amenorrheic runners were comparable with the eumenorrheic runners during the early follicular phase. Thus, submaximal exercise elicits significant increases in plasma AVP and PRA independent of menstrual phase and status. However, plasma ALDO is significantly elevated during the midluteal phase, exercise results in a greater response during this menstrual phase, and amenorrheic runners have elevated resting levels of ALDO.     

Cerebral blood flow is increased during controlled ovarian stimulation

Estrogen appears to enhance cerebral blood flow (CBF). An association between CBF and physiologically altered hormonal levels due to menstrual cycle, menopause, or exogenous manipulations such as ovariectomy or hormone replacement therapy has been demonstrated. The purpose of this study was to determine the association between ovarian stimulation and CBF in vivo by measuring blood flow in the internal carotid artery (ICA) after pituitary suppression and during controlled ovarian stimulation in women undergoing in vitro fertilization treatment cycles. ICA volume flows were measured by angle-independent dual-beam ultrasound Doppler in 12 women undergoing controlled ovarian stimulation. Measurements were performed after pituitary/ovarian suppression, in the late follicular phase, and at midluteal phase. Blood flow in the ICA increased by 22.2% and 32% in the late follicular and midluteal phases compared with the respective values obtained during ovarian suppression (P < 0.0005 and P < 0.0001, respectively). There was a significant correlation between increments in estrogen levels and increments in CBF when the late follicular phase was compared with the ovarian suppression period (r = 0.8, P < 0.001). Mean blood flow velocity significantly increased (by 15.7% and 16.9%, respectively) and cerebral vascular resistance significantly decreased (by 17.6% and 26.5%) during the late follicular and midluteal phases compared with respective measures during ovarian suppression. There was a significant correlation between an increase in estrogen levels and a decrease in cerebral vascular resistance when the late follicular phase was compared with the ovarian suppression period (r = -0.6, P < 0.05). These changes imply sex hormone-associated intracranial vasodilation leading to increased CBF during controlled ovarian stimulation.     

Physiological variability of fluid-regulation hormones in young women.

We tested the physiological reliability of plasma renin activity (PRA) and plasma concentrations of arginine vasopressin (P[AVP]), aldosterone (P[ALD]), and atrial natriuretic peptide (P[ANP]) in the early follicular phase and midluteal phases over the course of two menstrual cycles (n = 9 women, ages 25 +/- 1 yr). The reliability (Cronbach's alpha >/=0.80) of these hormones within a given phase of the cycle was tested 1) at rest, 2) after 2.5 h of dehydrating exercise, and 3) during a rehydration period. The mean hormone concentrations were similar within both the early follicular and midluteal phase tests; and the mean concentrations of P[ALD] and PRA for the three test conditions were significantly greater during the midluteal compared with the early follicular phase. Although Cronbach's alpha for resting and recovery P[ANP] were high (0.80 and 0.87, respectively), the resting and rehydration values for P[AVP], P[ALD], and PRA were variable between trials for the follicular (alpha from 0.49 to 0.55) and the luteal phase (alpha from 0.25 to 0. 66). Physiological reliability was better after dehydration for P[AVP] and PRA but remained low for P[ALD]. Although resting and recovery P[AVP], P[ALD], and PRA were not consistent within a given menstrual phase, the differences in the concentrations of these hormones between the different menstrual phases far exceeded the variability within the phases, indicating that the low within-phase reliability does not prevent the detection of menstrual phase-related differences in these hormonal variables.     

Menstrual cycle and sex affect hemodynamic responses to combined orthostatic and heat stress

Women have decreased orthostatic tolerance compared with men, and anecdotal evidence suggests women are more susceptible to orthostatic intolerance in warm environments. Because estrogen and progesterone affect numerous physiological variables that may alter orthostatic tolerance, the purpose of our study was to compare orthostatic tolerance across the menstrual cycle phases in women during combined orthostatic and heat stress and to compare these data with those of men. Eight normally menstruating women and eight males (22 +/- 4.0 and 23 +/- 3.5 yr, respectively) completed the protocol. Women were studied during their early follicular (EF), ovulatory (OV), and midluteal (ML) phases. Men were studied twice within 2-4 wk. Heart rate, cardiac output, blood pressure, core temperature (T(c)), and cutaneous vascular conductance (CVC) were measured during three head-up tilt tests, consisting of two tilts in the thermoneutral condition and one tilt after a 0.5 degrees C rise in T(c). There was no difference in orthostatic tolerance across the menstrual cycle phases, despite higher CVC in the ML phase after heating (EF, 42.3 +/- 4.8; OV, 40.1 +/- 3.7; ML, 57.5 +/- 4.5; P < 0.05). Orthostatic tolerance in the heat was greater in men than women (P < 0.05). These data suggest that although many physiological variables associated with blood pressure regulation fluctuate during the menstrual cycle, orthostatic tolerance in the heat remains unchanged. Additionally, our data support a clear sex difference in orthostatic tolerance and extend upon previous data to show that the sex difference in the heat is not attributable to fluctuating hormone profiles during the menstrual cycle.     

Haemodynamic responses to nonhypotensive central hypovolaemia induced by lower body negative pressure in men and women.

Haemodynamic responses to low levels of lower body negative pressure (LBNP) were investigated in two groups of healthy, normotensive volunteers (8 men and 8 women) during two repeated experimental runs on two occasions, the latter determined by the different phases of the menstrual cycle in the women. The data consisted of systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean blood pressure (MBP), pulse rate (fc), forearm blood flow (FBF) and forearm vascular conductance (FC). The resting cardiovascular status was similar in men and women, except that women had a significantly higher fc than men. LBNP (1.3, 2.7 and 4 kPa) had no significant effect on any BP variable or on fc. However, FBF and FC were reduced at all levels of LBNP. Significant overshoots in FBF and FC were seen in all subjects following the release of LBNP of 2.7 and 4 kPa and, in most cases, after release of LBNP of 1.3 kPa. There were no significant gender differences in any of the responses to LBNP. Furthermore, none of the cardiovascular variables measured showed significant differences between the follicular and luteal phases of the menstrual cycle in women, either at rest or during exposure to LBNP, and the responses in the men on the two occasions were not different. These findings indicate that gender differences in responses to LBNP hypothesized previously are not apparent during and after exposure to low levels of LBNP.     

Vestibulosympathetic reflex during the early follicular and midluteal phases of the menstrual cycle

Evidence suggests that both the arterial baroreflex and vestibulosympathetic reflex contribute to blood pressure regulation, and both autonomic reflexes integrate centrally in the medulla cardiovascular center. A previous report indicated increased sympathetic baroreflex sensitivity during the midluteal (ML) phase of the menstrual cycle compared with the early follicular (EF) phase. On the basis of this finding, we hypothesize an augmented vestibulosympathetic reflex during the ML phase of the menstrual cycle. Muscle sympathetic nerve activity (MSNA), mean arterial pressure (MAP), and heart rate responses to head-down rotation (HDR) were measured in 10 healthy females during the EF and ML phases of the menstrual cycle. Plasma estradiol (Delta72 +/- 13 pg/ml, P < 0.01) and progesterone (Delta8 +/- 2 ng/ml, P < 0.01) were significantly greater during the ML phase compared with the EF phase. The menstrual cycle did not alter resting MSNA, MAP, and heart rate (EF: 13 +/- 3 bursts/min, 80 +/- 2 mmHg, 65 +/- 2 beats/min vs. ML: 14 +/- 3 bursts/min, 81 +/- 3 mmHg, 64 +/- 3 beats/min). During the EF phase, HDR increased MSNA (Delta3 +/- 1 bursts/min, P < 0.02) but did not change MAP or heart rate (Delta0 +/- 1 mmHg and Delta1 +/- 1 beats/min). During the ML phase, HDR increased both MSNA and MAP (Delta4 +/- 1 bursts/min and Delta3 +/- 1 mmHg, P < 0.04) with no change in heart rate (Delta0 +/- 1 beats/min). MSNA and heart rate responses to HDR were not different between the EF and ML phases, but MAP responses to HDR were augmented during the ML phase (P < 0.03). Our results demonstrate that the menstrual cycle does not influence the vestibulosympathetic reflex but appears to alter MAP responses to HDR during the ML phase.     

月经周期对女性睡眠-觉醒和静息-活动的影响

目前有关月经周期对睡眠影响的研究结果并不一致,而对月经周期中昼夜睡眠-觉醒及静息-活动节律尚缺乏系统性的研究.本研究旨在观察正常育龄期女性月经周期中睡眠-觉醒及静息-活动昼夜节律的变化.我们采用静息-活动监测仪(actigraphy)和睡眠日志,调查了12个自然生活状态下健康育龄期妇女在月经周期不同阶段,即行经期、围排卵期、黄体早期及黄体晚期中睡眠与活动节律的变化.结果显示,睡眠-觉醒节律参数在四期之间无统计学显著差异;而静息-活动节律方面,所有受试女性静息-活动节律的平均日周期长度为(24.01±0.29)h,并且四期之间无显著性差异.行经期日间稳定系数(interdaily stability,IS)比黄体早期显著增加(P＜0.05).黄体早期日间活动开始时间明显较黄体晚期提前(P＜0.05);黄体早期的活动峰值时相比围排卵期显著提前(P＜0.05).月经周期可以影响静息-活动昼夜节律时相.而总体静息-活动数量与质量未发生显著变化;健康育龄期妇女在月经周期的各阶段中睡眠-觉醒节律亦无明显变异.     

Cyclical changes in the renin-angiotensin-aldosterone system during the menstrual cycle of the baboon (Papio hamadryas)

Abstract: This study characterizes the renin-angiotensin-aldosterone system during the normal menstrual cycle in the baboon. Ten animals received a daily dose of an ACE inhibitor or placebo in a randomized blind cross-over design. Data were obtained during the mid-follicular and early luteal phases of normal non-pregnant menstrual cycles. All examinations and blood collections were performed with ketamine sedation: 7–kg by im injection. Blood pressure was recorded by sphygmomanometer. Serum ACE activity was measured by spectrophotometry. Aldosterone (ALDO), angiotensin I (AI), and angiotensin II (AII) were measured by radioimmunoassay. Plasma renin activity (PRA) was measured by AI generation. The renin-angiotensin-aldosterone system was found to be activated in the follicular phase and suppressed during the luteal phase of the normal non-pregnant menstrual cycle in the baboon.     

Plasma alpha-melanocyte-stimulating hormone during the menstrual cycle in women

alpha-Melanocyte-stimulating hormone (alpha-MSH) and adrenocorticotropin (ACTH) immunoreactivity (IR) was measured in the blood of 22 healthy women with normal ovulatory process in the early and late follicular (near to ovulation) phases and in the early luteal phase of the menstrual cycle. Plasma alpha-MSH IR ranged from undetectable values to 81.3 pg/ml, the highest levels being found in the late follicular phase (15.52 +/- 4.16 pg/ml). In contrast, plasma ACTH IR was always detectable (range: 18.5-63.2 pg/ml), but its concentration did not differ significantly between the 3 phases of the menstrual cycle. High-pressure liquid chromatography fractionation of Sep pak C18-purified alpha-MSH IR revealed in all 3 phases the presence of 3 major peaks of alpha-MSH IR, coeluting with desacetyl-alpha-MSH, alpha-MSH and diacetyl-alpha-MSH, respectively. The most abundant peak always coeluted with authentic desacetyl-alpha-MSH, and the ratio between this deacetylated and the other 2 acetylated forms was similar in the 2 follicular phases (1:1.25 and 1:1.16 in the early and late phase, respectively), but significantly different in the luteal phase (1:0.48). The fluctuations in plasma concentration of the above MSH-related peptides suggest that different rates of alpha-MSH acetylation and release take place in the pituitary gland depending on the phase of the menstrual cycle.