Function and reactivity of the microvascular bed in human neuroses

By contact microscopy the state and reactivity of the capillary bed (capillaries of the cheek mucosa) were studied in neurotic patients with different levels of arterial pressure (AP). It has been shown that at constant AP capillariscopic parameters (diameter, length and number of capillaries in the visual field) are relatively stable. Neuroses with hypertension are characterized by uneven (more expressed in arterioles) contraction of the capillaries, accelerated development and greater duration of reactions to the mental stress and applications of adrenaline and noradrenaline solutions in comparison with healthy persons. In hypotension, uniform capillaries contraction and slower development of the above reactions are observed.     

The problem of adaptation and oscillatory processes in the microvascular bed

Healthy people (n = 16), patients with autonomic dystonia syndrome (n = 38), and patients with traumatic rupture of the median nerve before and after nerve suture (n = 28) were examined by laser Doppler flowmetry (LDF) with a computer wavelet analysis of blood flow oscillations. Functional states (FSs) of the microcirculatory bed wеre assessed using energetic and information indices of microvascular blood flow oscillations. The variation coefficient and the information regime (multistable or resonance) were used as key characteristics. Oscillatory processes are an integral part of adaptation and the FS formation in the microvascular bed. FSs were classified as adaptive, hyperadaptive, hypoadaptive, and failure of adaptation. Because supporting the optimal function of nutritive microvessels is a leading component of the adaptation process, FSs of nutritive and nonnutritive microvessels may differ. A selective contribution of the autonomic sympathetic regulatory channel was related to maintaining considerable hyperadaptation in the microvascular bed with overstrain or marked overstrain of regulatory systems, as in emotional stress. Hypoadaptive FSs formed when skin blood flow increased, an excess decrease in flow resistance was unnecessary, and especially when regulatory factors were in deficiency, e.g., in neurodystrophic syndrome.     

Aging features in functioning of skin microvascular bed in humans

The state of skin microcirculation system has been studied in healthy volunteers aged from 20 to 77, using laser Doppler flowmetry. To reveal the reaction of microvascular bed in response to short-term ischemia, occlusive test has been carried out. During experiment the age-induced reduction of microcirculation index has been observed at rest. In response to stopping occlusion the 3.5--4-aliquot increase of microcirculation index has been revealed during reactive post-occlusive hyperemia in all age groups. The data obtained suggest maintenance of high reserve resources of skin microcirculation in ageing in response to ischemia.     

Morphofunctional asymmetry of the microvascular bed of the rabbit concha auriculae

Microvessels of rabbit ears chamber and blood samples drawn from the internal ear vein after 30 min ischemia were studied. In the initial state the length of the left ear microvascular bed was 1.5 times higher, mean microvessel diameter 14.6% less, apparent viscosity of outflowing blood 16.8% less, RBC concentration per volume unity of blood 8% higher, RBC electrophoretic mobility 13.7% higher than those in the right one. It was shown that the left microvessel bed responds to the ischemia with the 13.2% increase of its length and 13.6% increase of the outflowing blood viscosity, the right one--with the 9.7% increase of microvessel diameter and 7.9% decrease of the viscosity.     

The Histophysiology of the Prolactin Cell in Non-Mammalian Vertebrates

With the exception of the agnathan fishes, a prolactin cellhas been identified in all vertebrates in which it has beensought. This review examines the structure of the prolactin-producingpituitary cell in non-mammalian vertebrates, the manner in whichit responds to natural and artificial stimuli, and its controlby neural and humoral factors. Fundamental similarities anddifferences are described in an attempt to understand betterits method of operation. Given our present state of knowledge, there is, among all theapparent diversity, a similarity in the basic structure andmorphological response of this cell in teleosts, amphibians,reptiles, and birds. One can identify and speak with relativecertainty about a specific adenohypophysial cell called a "prolactincell." More profound differences may be found at the level ofcontrol mechanisms, chemistry of the hormone(s), and the natureof receptivity and response of target tissues. It appears that although there are basic similarities in thedesign of the prolactin cell, the systems that control its activitiesmay differ and the similar products produced by the cell maybe used toward different ends.     

Ultrastructure of the venous ampulla in the interradicular microvascular bed of the mandibular molars of Mus musculus

The interradicular periodontal ligament of mandibular molars contains an apparently unique dilated vessel straddling the interradicular alveolar bone. This structure is designated a venous ampulla. The vessel possesses a luminal length and width of approximately 200 X 100 microns, respectively. Ultrastructurally, the endothelium has an average thickness of 0.35 micron, a continuous basement membrane, and an incomplete layer of pericytes. Open endothelial junctions are not present. The anatomy of the vessel wall differs markedly on the dental- and bone-related aspects. Calculated ratios for the luminal diameter to wall thickness vary from 1:80 to 1:150. Postcapillary-sized limbs from this vessel drain into the interradicular septum of bone and the ligament microvascular bed. Arterial supply to the ampulla is provided via arteriovenous anastomoses characterized by their association with myelinated and unmyelinated nerve groups. Oxytalan fibers are present throughout the wall of the venous ampulla, penetrating to the abluminal side of the endothelium where they are associated with unmyelinated axons and free nerve endings. Elsewhere, oxytalan fibers are related to the arteriovenous anastomoses and their accompanying myelinated and unmyelinated nerves located adjacent to the endothelium. Pericytes form membranous contacts with the endothelium of the arteriovenous anastomoses and have processes penetrating the endothelium basement membrane.     

Comparison of vascular hemodynamics in experimental models of microvascular anastomoses

Blood flow was measured in the canine saphenous artery using electromagnetic flowmetry. Significant increase in blood flow was noted after occlusion of the distal femoral artery. However, after raising a saphenous island flap there was no significant change in the blood flow before and after distal femoral artery occlusion. The flap peripheral resistance and blood flow were compared after end-to-end and end-to-side anastomosis and no statistical difference was noted.     

Histophysiology of hair follicles: current concept

Hair follicle histophysiology importance isn't limited by hair role in psychosocial consequences. More scientists consider the hair follicle as an attractive system for studying major biological phenomena because the hair follicle is a regenerating system. In this review we revisit the current information about histophysiology and control of hair follicle cycling. All mature follicles undergo a growth cycle consisting of following phases: growth (anagen), regression (catagen) and rest (telogen). We attempt to integrate the morphology with the physiology and molecular biology. Hair follicles are influenced by environmental, systemic and local factors. The most interesting point of this problem is discussed--an integral regulation of hair follicle cycle by systemic, intertissue and intercellular interactions.     

Ultrastructural changes in the sympathetic ganglia in experimental burn trauma

Ultrastructural changes of neurones of sympathetic vegetative nervous ganglia were studied in 15 white male rats at an age of 5-7 months. In the dynamic of postmortem changes disorders typical of hypoxic conditions of the chest predominated.