scholarly journals Counter Current Transfer of Oxytocin from the Venous Blood of the Perihypophyseal Cavernous Sinus to the Arterial Blood of Carotid Rete Supplying the Hypophysis and Brain Depends on the Phase of the Estrous Cycle in Pigs1

1995 ◽  
Vol 52 (1) ◽  
pp. 139-144 ◽  
Author(s):  
W. Grzegorzewski ◽  
J. Skipor ◽  
B. Wasowska ◽  
T. Krzymowski
Keyword(s):  
Estrous Cycle ◽  
Cavernous Sinus ◽  
Venous Blood ◽  
Current Transfer ◽  
Arterial Blood ◽  
Counter Current

scholarly journals Counter-current transfer in reproductive biology

Reproduction ◽  
2005 ◽  
Vol 129 (1) ◽  
pp. 9-18 ◽  
Author(s):  
N Einer-Jensen ◽  
RHF Hunter
Keyword(s):  
Venous Blood ◽  
Feedback Regulation ◽  
Systemic Circulation ◽  
Reproductive Organs ◽  
General Distribution ◽  
Current Transfer ◽  
Local Cooling ◽  
Arterial Blood ◽  
Local Feedback ◽  
Counter Current

Heat and substances, including gases, steroids and peptide hormones, can pass from venous blood, interstitial fluid and lymph to the arterial blood; the process is called local counter-current transfer. It has been found in various reproductive organs in many animal species and in man: from the testis to the testis and epididymis; from the ovary to the ovary, tube and tubal corner of the uterus; from the tube and uterus to the ovary; from vagina to uterus; and even between brain blood vessels. Local transfer within the ovary has also been found. Local cooling that creates temperature gradients between organs or within an organ is one aspect of the transfer. Physiologically, the transfer also facilitates local feedback regulation of organ function in a process situated between general distribution of hormones through the systemic circulation and paracrine regulation. Counter-current transfer of drugs after local application opens up new possibilities for treatment.

scholarly journals Topsy-turvy: turning the counter-current heat exchange of leatherback turtles upside down

2015 ◽  
Vol 11 (10) ◽  
pp. 20150592 ◽  
Author(s):  
John Davenport ◽  
T. Todd Jones ◽  
Thierry M. Work ◽  
George H. Balazs
Keyword(s):  
Heat Exchangers ◽  
Venous Blood ◽  
Vascular Supply ◽  
The Body ◽  
Leatherback Turtles ◽  
The Core ◽  
Arterial Blood ◽  
Hip Muscles ◽  
Counter Current ◽  
Current Heat

Counter-current heat exchangers associated with appendages of endotherms feature bundles of closely applied arteriovenous vessels. The accepted paradigm is that heat from warm arterial blood travelling into the appendage crosses into cool venous blood returning to the body. High core temperature is maintained, but the appendage functions at low temperature. Leatherback turtles have elevated core temperatures in cold seawater and arteriovenous plexuses at the roots of all four limbs. We demonstrate that plexuses of the hindlimbs are situated wholly within the hip musculature, and that, at the distal ends of the plexuses, most blood vessels supply or drain the hip muscles, with little distal vascular supply to, or drainage from the limb blades. Venous blood entering a plexus will therefore be drained from active locomotory muscles that are overlaid by thick blubber when the adults are foraging in cold temperate waters. Plexuses maintain high limb muscle temperature and avoid excessive loss of heat to the core, the reverse of the accepted paradigm. Plexuses protect the core from overheating generated by muscular thermogenesis during nesting.

Parametric Studies on the Three-Layer Microcirculatory Model for Surface Tissue Energy Exchange

1986 ◽  
Vol 108 (1) ◽  
pp. 89-96 ◽  
Author(s):  
Z. Dagan ◽  
S. Weinbaum ◽  
L. M. Jiji
Keyword(s):  
Venous Blood ◽  
Thermal Characteristics ◽  
Tissue Temperature ◽  
Capillary Perfusion ◽  
Metabolic Heat ◽  
Blood Temperature ◽  
Arterial Blood ◽  
Parametric Studies ◽  
Counter Current ◽  
Cutaneous Blood

The new three-layer microvascular mathematical model for surface tissue heat transfer developed in [1, 2], which is based on detailed vascular casts and tissue temperature measurements in the rabbit thigh, is used to investigate the thermal characteristics of surface tissue under a wide variety of physiological conditions. Studies are carried out to examine the effects of vascular configuration, arterial blood supply rate, distribution of capillary perfusion, cutaneous blood circulation and metabolic heat production on the average tissue temperature profile, the local arterial-venous blood temperature difference in the thermally significant counter-current vessels, and surface heat flux.

Cold-induced shivering in men with thermoneutral skin temperatures

1976 ◽  
Vol 41 (2) ◽  
pp. 142-145 ◽  
Author(s):  
A. G. Buguet ◽  
S. D. Livingstone ◽  
L. D. Reed ◽  
R. E. Limmer
Keyword(s):  
Venous Blood ◽  
Electromyographic Activity ◽  
Jugular Veins ◽  
Arterial Blood ◽  
Air Temperatures ◽  
Cold Room ◽  
Warm Blood ◽  
The Common ◽  
Counter Current ◽  
Skin Temperatures

Twenty-two male Caucasians, aged 20–47 yr, were exposed in a cold room to air temperatures of -33 degrees C while lying in sleeping bags for 2 h. Skin and rectal temperatures as well as electromyographic activity of the chin, forearm, and thigh, were recorded. Shivering occurred in all the subjects, even though skin temperatures were maintained between 31 and 33 degrees C. It is suggested that a counter-current heat exchange occurs whereby the warm blood of the common carotid artery is cooled by cool venous blood in the jugular veins. This cooled arterial blood, in irrigating the hypothalamus, causes shivering.

scholarly journals The rostral epidural rete mirabile of the llama as a place of retrograde transport of various substances – anatomical basics

2021 ◽  
Vol 9 (3) ◽  
pp. 105-109
Author(s):  
Maciej Zdun ◽  
Arkadiusz Grzeczka ◽  
Marcin Zawadzki ◽  
Hieronim Frąckowiak
Keyword(s):  
Cavernous Sinus ◽  
Carotid Arteries ◽  
Venous Blood ◽  
Retrograde Transport ◽  
External Jugular Vein ◽  
Lateral Part ◽  
Rete Mirabile ◽  
Arterial Blood ◽  
Common Carotid Arteries ◽  
Vascular Corrosion Casts

Abstract The aim of this study was to analyse the structure of the rostral epidural rete mirabile in the llama. Some specimens were prepared by injecting stained chemically cured acrylic into the bilateral common carotid arteries. After about 1 month received vascular corrosion casts on the bone scaffold. Some specimens made using red and blue latex introduced into the bilateral common carotid arteries and the bilateral external jugular vein. The rostral epidural rete mirabile is a well-developed, bilateral structure composed of numerous arteries, which are multiply anastomosed with each other. The cranial section of the rete is asymmetrical. Its lateral part is much better developed, because there are rostral branches to the rostral epidural rete mirabile at this point. The arterial vessels are not accompanied by homonymous veins. However, the arteries of the rostral epidural rete mirabile are accompanied by venous vessels of the cavernous sinus. That rete plays an important role in selective brain cooling, the conservation of body water, and retrograde transport of neurotransmitters. CO, GnRH, beta-endorphin, progesterone, testosterone, oxytocin, LHRH and dopamine diffuse from the venous blood of the cavernous sinus to the arterial blood of the rostral epidural rete mirabile.

Arterio-Venous Differences in the Components of the Fibrinolytic Enzyme System

1966 ◽  
Vol 16 (01/02) ◽  
pp. 032-037 ◽  
Author(s):  
D Ogston ◽  
C. M Ogston ◽  
N. B Bennett
Keyword(s):  
Plasminogen Activator ◽  
Enzyme System ◽  
Venous Blood ◽  
Fibrinolytic Enzyme ◽  
Blood Levels ◽  
Activator Concentration ◽  
Blood Samples ◽  
Arterial Blood ◽  
Male Subjects

Summary1. The concentration of the major components of the fibrinolytic enzyme system was compared in venous and arterial blood samples from male subjects.2. The plasminogen activator concentration was higher in venous blood and the arterio-venous difference increased as its concentration rose, but the ratio of the arterial to venous level remained constant.3. No arterio-venous difference was found for anti-urokinase activity, antiplasmin, plasminogen and fibrinogen.4. It is concluded that venous blood determinations of the components of the fibrinolytic enzyme system reflect satisfactorily arterial blood levels.

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