Introduction: a brief history of capillaries and some examples of their apparently strange behaviour

The Vascular Factor Plays the Main Role in the Cause of Pain in Men with Chronic Prostatitis and Chronic Pelvic Pain Syndrome: The Results of Clinical Trial on Thermobalancing Therapy

Chronic pain in patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), NIH category III is difficult to treat without understanding its cause. The main symptom of chronic prostatitis is pain. In this study, we would like to explain the origin of pain in men with CP/CPPS and its therapy. Forty-five patients with CP/CPPS have received thermobalancing therapy (TT) enabled by Dr Allen's therapeutic device (DATD) for six months as mono-therapy. The control group comprised 45 men with CP/CPPS did not receive TT. Before and after six months the National Institute of Health Chronic Prostatitis Symptom Index (NIH-CPSI) scores, prostatic volume (PV) by ultrasound measurement and uroflowmetry (Q_max) were compared between the groups. Baseline characteristics have shown no difference. After TT, significant improvements in pain score (p < 0.001), quality of life index (QoL) (p < 0.001), decrease of PV (p < 0.001), and increase Q_max (p < 0.001) were determined. There were not noteworthy changes in the control group. Chronic pain due to CP/CPPS happens as a consequence and challenges at the capillary level, namely pathological capillary activity. In response to initial triggers-such as inflammation, cold, psychological and other factors-constriction and spontaneous expansion of capillaries follows, creating a continuous secondary trigger-i.e., the micro-focus of hypothermia-which in turn provokes expansion of capillaries. The additional tissue due to vascular changes into the prostate increases pressure on nociceptors causing pain. TT relieves chronic pelvic pain by eliminating the lasting focus of hypothermia in the affected prostate tissue.

Dermal capillary clearance: physiology and modeling

Substances applied to the skin surface may permeate deeper tissue layers and pass into the body's systemic circulation by entering blood or lymphatic vessels in the dermis. The purpose of this review is an in-depth analysis of the dermal clearance/exchange process and its constituents: transport through the interstitium, permeability of the microvascular barrier and removal via the circulation. We adapt an 'engineering' viewpoint with emphasis on quantifying the dermal microcirculatory physiology, providing the theoretical framework for the physics of key transport processes and reviewing the available computational clearance models in a comparative manner. Selected experimental data which may serve as valuable input to modeling attempts are also reported.

A compartmental capillary, convolution integration model to investigate nutrient transport and metabolism in vivo from paired indicator/nutrient dilution curves

Thirty-three paired indicator/nutrient dilution curves across the mammary glands of four cows were obtained after rapid injection of para-aminohippuric acid (PAH) plus glucose into the external iliac artery. For the measurement of extracellular volume and kinetics of nutrient uptake from indicator dilution curves, several models of solute dispersion and disappearance have been proposed. The Crone-Renkin models of exchange in a single capillary assume negligible washout of solutes from the extracellular space and do not describe entire dilution curves. The Goresky models include a distribution of capillary transit times to generate whole system outflow profiles but require two indicators to parametize extracellular behavior. A compartmental capillary, convolution integration model is proposed that uses one indicator to account for the extracellular behavior of the nutrient after a paired indicator/nutrient injection. With the use of an iterative approach to least squares, unique solutions for nonexchanging vessel transit time t(mu) and its variance sigma were obtained from all 33 PAH curves. The average of heterogeneous vascular transit times was approximated as 2sigma = 8.5 s. The remainder of indicator dispersion was considered to be due to washout from a well-mixed compartment representing extracellular space that had an estimated volume of 5.5 liters or 24% of mammary gland weight. More than 99% of the variation in the time course of venous PAH concentration after rapid injection into the arterial supply of the mammary glands was explained in an unbiased manner by partitioning the organ into a heterogeneous nonexchanging vessel subsystem and a well-mixed compartmental capillary subsystem.

The microvasculature as a dynamic regulator of volume and solute exchange

1. It has long been held that the microvessels are passive pipes through which the formed elements of blood and plasma course and from which exchange occurs. Physiological and structural data from vascular cells in culture to whole organs strongly support the notion that microvessels, whether in their arrangement as networks, in their microvascular phenotypic subtypes or with regard to their permeability properties, are anything but static. 2. Examples from different models, organs and species are presented to illustrate the spatial and dynamic nature of the microvasculature. 3. Given that the ultimate goal of this cardiovascular research is to apply what is learned from component parts of the microvasculature to understand integrated tissue function, examples of the danger of generalizing results from limited studies are presented. 4. Finally, accurate interpretation of most of the research in this area is predicated on the assumption that probe molecules, rendered visible by the binding of dyes, are biologically inert. 5. We present data demonstrating that some dyes used widely in microvascular studies can alter the barrier under study and/or alter the physicochemical characteristics of the molecule to which they were bound.