Drug delivery to the brain for the treatment of pathologies with a CNS component is a significant clinical challenge. P‐glycoprotein (PgP), a drug efflux pump in the endothelial cell membrane, is a major factor in preventing therapeutics from crossing the blood‐brain barrier (BBB). Identifying PgP regulatory mechanisms is key to developing agents to modulate PgP activity. Previously, we found that PgP trafficking was altered concomitant with increased PgP activity and disassembly of high molecular weight PgP‐containing complexes during acute peripheral inflammatory pain. These data suggest that PgP activity is post‐translationally regulated at the BBB. The goal of the current study was to identify proteins that co‐localize with PgP in rat brain microvessel endothelial cell membrane microdomains and use the data to suggest potential regulatory mechanisms. Using new density gradients of microvessel homogenates, we identified two unique pools (1,2) of PgP in membrane fractions. Caveolar constituents, caveolin1, cavin1, and cavin2, co‐localized with PgP in these fractions indicating the two pools contained caveolae. A chaperone (Hsc71), protein disulfide isomerase and endosomal/lysosomal sorting proteins (Rab5, Rab11a) also co‐fractionated with PgP in the gradients. These data suggest signaling pathways with a potential role in post‐translational regulation of PgP activity at the BBB.
In this study, distribution of metal accumulation and their biological changes of Indian mustard plants (Brassica nigra L.) grown in
soil irrigated with different concentration of rayon grade paper effluent (RGPE, 25%, 50%, 75%, 100%, v/v) were studied. A
pronounced effect was recorded at 50% (v/v) RGPE on germination of seeds, amylase activity and other growth parameters in
Indian mustard plants. An increase in the chlorophyll and protein contents was also recorded at <50% (v/v) RGPE followed by a
decrease at higher concentrations of RGPE (>75%). A significant increase lipid peroxidation was recorded, which was evidenced by
the increased malondialdehyde (MDA) content in shoot, leaves and seeds in tested plant at all the concentrations of RGPE. This
Indian mustard plants (Brassica nigra L.) are well adapted for tolerance of significant amount of heavy metals due to increased level
of antioxidants (cysteine and ascorbic acid) in root shoot and leaves of treated plants at all concentration of RGPE. Moreover, it is
also important that RGPE should be treated to bring down the metal concentration well within the prescribed limit prior to use in
agricultural soil for ferti-irrigation. 相似文献
Eleven germplasms of faba bean seeds from four agroclimatic regions of Bihar, India, have been investigated to estimate their nutritional (soluble protein, free amino acids, starch, reducing and non reducing sugar, total soluble sugar) and antinutritional (total extractable phenol and condensed tannin/proanthocyanidin) parameters. These parameters were found in varying concentration in all genotypes studied. The highest concentration of total extractable phenol and proanthocyanidin (condensed tannin) (2.56 and 1.59 % leucocyanidin equivalents respectively on dry matter basis) were found in Samastipur while the lowest from Patna (0.95 and 0.426 % leucocyanidin equivalent on dry matter basis). The different nutritional parameters were also found to be in variable concentration among different germplasms viz. total soluble protein ≈ 20–32 %, free amino acids ≈ 188–348 mg/100 g, starch ≈ 27–33 %, reducing sugars ≈ 85–188 mg/100 g, non reducing sugars ≈ 0.7–1.7 % and total soluble sugars ≈ 0.8–1.9 %. 相似文献
Rodent ovariectomy is an experimental method to eliminate the main source of sexual
steroids. This work explored for the first time the ovariectomy temporal changes induced
in the hemostatic coagulation markers: prothrombin time (PT), activated partial
thromboplastin time (aPTT), thrombin time (TT), and fibrinogen concentration (FIB) along
with uterine weight on adult female CD1 mice and Wistar rats. Uterine weight (Uw) was
assessed before ovariectomy (control), and 1, 3, 5, 7, 9, 16, and 21 days after surgery.
PT, aPTT, TT and FIB were estimated the same days, using reported standard techniques.
Ovariectomy decreased Uw, since day 1; and from day 10 to 21 reached the lowest values for
both species. After day 1, mice hemostatic parameters changed (PT +10%,
P<0.05; aPTT +53%, P<0.05; TT −24%,
P<0.05; FIB +67%, P<0.05). Rats showed
significant changes only in TT and FIB (TT −13%, P<0.001; FIB +65%,
P<0.001). Neither mice PT, aPTT and TT, recovered control values
after 21 days. In the rats from day 5 to 16 aPTT diminished (18–23%,
P<0.05) recovering to control values on day 21, TT after 9 days and PT
on day 16. In both species, FIB returned to its control values after 9 days. Ovariectomy
differentially altered the PT hemostatic parameter of mice and rats indicating a
non-equivalence among both species behaviour for experimental studies of blood
coagulation. 相似文献
Haptoglobin (Hp), serum amyloid A (SAA), C-reactive protein (CRP), white blood cells
(WBC), reactive oxygen metabolites (ROMs), the antioxidant barrier (Oxy-adsorbent) and
thiol groups of plasma compounds (SHp) were measured in ten dogs that had been transported
a distance of about 230 km within 2 h (experimental group) and in ten dogs that had not
been subjected to road transportation (control group). Blood was collected via cephalic
venipuncture before road transportation (T0), after road transportation (T1), and more
than 6 (T6) and 24 (T24) hours after road transportation in the experimental group (Group
A) and at the same time points in the control group (Group B). The GLM (general linear
model) Repeated Measures procedure showed a significant difference between the two groups
(P<0.0001) and a significant rise (P<0.0001) in
the concentrations of Hp, SAA, CRP, WBC, ROMs, Oxy-adsorbent and SHp after road
transportation in Group A, underlining that physiological and homeostatic mechanisms are
modified differently at various sampling times. 相似文献
Global change affects individual phenotypes and biotic interactions, which can have cascading effects up to the ecosystem level. However, the role of environmentally induced phenotypic plasticity in species interactions is poorly understood, leaving a substantial gap in our knowledge of the impacts of global change on ecosystems. Using a cladoceran–dragonfly system, we experimentally investigated the effects of thermal acclimation, acute temperature change and enrichment on predator functional response and metabolic rate. Using our experimental data, we next parameterized a population dynamics model to determine the consequences of these effects on trophic interaction strength and food‐chain stability. We found that (1) predation and metabolic rates of the dragonfly larvae increase with acute warming, (2) warm‐acclimated larvae have a higher maximum predation rate than cold‐acclimated ones, and (3) long‐term interaction strength increases with enrichment but decreases with both acclimation and acute temperatures. Overall, our experimental results show that thermal acclimation can buffer negative impacts of environmental change on predators and increase food‐web stability and persistence. We conclude that the effect of acclimation and, more generally, phenotypic plasticity on trophic interactions should not be overlooked if we aim to understand the effects of climate change and enrichment on species interaction strength and food‐web stability. 相似文献