Anatomic variations of the nasolabial fold.

The nasolabial fold varies considerably from person to person. Three main groups may be distinguished: convex, concave, and straight. It is the muscles of smiling that are directly responsible for the shape and depth of the fold, and in their absence of function, as in facial palsy, the nasolabial fold disappears. Cadavers were selected in accordance with the nasolabial fold they presented and were dissected to analyze the difference in underlying anatomy between one fold shape in one cadaver and another fold shape in another. The study demonstrates that the nasolabial fold is the result of a conflict between soft and dynamic tissues of the middle face or an interaction between the skin and fat envelope on one side and the underlying muscles on the other. The greater this conflict, the more excess there is of cheek skin and the more pronounced a nasolabial fold. The mechanism that creates the nasolabial fold and the anatomy of the fold are described in this paper.     

Prostacyclin increases portal venous flow

Prostacyclin (PGI₂) is a potent vasolidator and is a potential therapeutic agent to increase blood flow during several disease states. PGI₂ is alos elevated in plasma during sepsis or pancreatitis. The hemodynamic effect of PGI₂ has not been investigated with regard to the portal venous system. In five anesthetized swine, cardiac output (CO), central venous pressure (CVP), femoral artery pressure (FAP), heart rate (HR), pulmonary artery pressure (PAP), portal venous flow (PoVF), and portal venous pressure (PoVP) were measured before and after increasing doses of PGI₂. The infusions were then repeated after atropine administration. The previously reported effects on the peripheral and pulmonary vascular systems were confirmed. after an injection of 0.5 to 5.0 ug/kg of PGI₂ into the left atrium, a significant decline in CO, FAP, and PAP occured. Atropinization further depressed CO. The most marked effecr of PGI₂, however, was an increase in PoVF without a change in PoVP. This effect was more pronounced when atropine was administered. In anethetized swine, PGI₂ is a potent vasodilator in all vascular beds, including the portal venous system. These hemodynamic changes should be realized when exogenous PGI₂ is considered as a therapeutic agent or when endogenous PGI₂ might increase in association with disease states like pancreatitis or sepsis.     

Anatomic transformation of the lymphatic bed of the small intestine following immunization]

The experimental investigation of the lymphatic bed of the small intestine after immunization was performed in 15 rabbits. Ten rabbits were taken as control. The rabbits were immunized by administration of kidney antigen with the complete Freund adjuvant. The animals were killed on the 7-8th days after two cycles of immunization, three injections in each cycle. The interval between the injections was three days, between the cycles - one month. Polychrome injection of arteries and veins was made. The lymphatic bed was filled with Gerota's mass. The chylus sinuses, lymph capillaries and vessels of experimental animals were found to be dilated 2-6 times as compared with normal. There appear many blind processes on the walls of lymph capillaries and vessels. Intraorganic lymphatic pathways were more dilated as compared with extraorganic. The ileum was found to be more reactive in immunization than other two parts of the small intestine.     

Anatomic study of the venous drainage architecture of the forearm skin and subcutaneous tissue

The venous anatomy of the forearm skin was examined radiographically in 15 fresh cadavers that had been injected systemically with a lead oxide-gelatin mixture. In 10 specimens, the forearm skin was divided into the skin and superficial adipofascial layer and the deep adipofascial layer. Five specimens were radiographed stereoscopically. Despite the thinness of the skin and subcutaneous tissue of the forearm, the cutaneous vein was seen three-dimensionally. Judging from the architecture and direction of the venous valves, most of the venous blood that had perfused the dermis was believed to: (1) pool in a venous network located in the superficial zone of the skin and subcutaneous tissue, (2) flow chiefly in the accessory cephalic and median antebrachial veins, and (3) enter the cephalic and basilic veins near the antecubital fossa. Venae comitantes of the septocutaneous and musculocutaneous perforators of the radial or ulnar arteries were thought to be only bypasses to the deep vein.     

Structural features of the intrinsic venous bed of the human urinary bladder

The intraorganic veins of the human urinary bladder have been studied in a vast sectional material. The veins within the organ make an enormous multilayered plexus which is differently organized in various layers of its wall. Abundant anastomoses, multiplicated ways for outflow from every layer, manifested interactions between the venous plexuses are specific for the intraorganic venous bed of the urinary bladder. The structures for an active regulating the hemomicrocirculatory blood stream are widely presented in the urinary bladder. In its every tunic certain specific morpho-functional features for organization and adaptation of the intraorganic venous bed are revealed.     

Metabolic effects of long-term diversion of renal venous blood into the portal system

In 7 splenectomized dogs a left renal vein-splenic vein anastomosis was performed and the right kidney removed. Eighteen to twenty-four months after portalization of renal venous blood no significant alterations of liver function tests were observed. Long-term diversion of renal venous blood into the liver was followed by a slight increase of creatinine and 25-OH-D, a decrease of alpha-amino acid nitrogen in blood plasma and of plasma renin activity in peripheral blood, by signs of slight carbohydrate intolerance despite hyperinsulinaemia, and a slight decrease of erythrocyte count. No influence of this procedure on plasma proteins, lipids, electrolytes, aldosterone and cortisol was found. No morphological abnormalities in the liver and kidney tissue were found.     

Effect of venous congestion on the microcirculatory bed of rat adrenal glands]

Early effect of experimentally induced venous congestion on the rat adrenals is evident in dynamical changes in the microcirculatory bed of the glands. As morphometric data demonstrate, the greatest changes take place in blood vessels of the cortical substance: the capillary diameters are dilated in all the zones, the thickness of the wall in subcapsular and capsular arterioles increases at the expense of hypertrophic smooth muscle elements. Subsequently, venous-arteriolar reaction develops, with capillary diameter approaching the initial size. The data obtained are discussed.     

Morphofunctional characteristics of the venous bed of the myocardium in response to acute hypoxia

Anatomical redistribution of blood outflow between the superficial and deep pathways is motivated, changes in microvessels under a circular hypoxia are presented. General peculiarities in structure of the sources for both pathways are ascertained, as well as specific differences stipulated by the physiological role of the cardiac venous sinusis.     

Effect of hepatic venous sphincter contraction on transmission of central venous pressure to lobar and portal pressure

In dogs anesthetized with pentobarbital, central vena caval pressure (CVP), portal venous pressure (PVP), and intrahepatic lobar venous pressure (proximal to the hepatic venous sphincters) were measured. The objective was to determine some characteristics of the intrahepatic vascular resistance sites (proximal and distal to the hepatic venous sphincters) including testing predictions made using a recent mathematical model of distensible hepatic venous resistance. The stimulus used was a brief rise in CVP produced by transient occlusion of the thoracic vena cava in control state and when vascular resistance was elevated by infusions of norepinephrine or histamine, or by nerve stimulation. The percent transmission of the downstream pressure rise to upstream sites past areas of vascular resistance was elevated. Even small increments in CVP are partially transmitted upstream. The data are incompatible with the vascular waterfall phenomenon which predicts that venous pressure increments are not transmitted upstream until a critical pressure is overcome and then further increments would be 100% transmitted. The hepatic sphincters show the following characteristics. First, small rises in CVP are transmitted less than large elevations; as the CVP rises, the sphincters passively distend and allow a greater percent transmission upstream, thus a large rise in CVP is more fully transmitted than a small rise in CVP. Second, the amount of pressure transmission upstream is determined by the vascular resistance across which the pressure is transmitted. As nerves, norepinephrine, or histamine cause the hepatic sphincters to contract, the percent transmission becomes less and the distensibility of the sphincters is reduced. Similar characteristics are shown for the "presinusoidal" vascular resistance and the hepatic venous sphincter resistance.(ABSTRACT TRUNCATED AT 250 WORDS)     

Intermittent sampling of portal venous blood and bile from guinea pigs

A technique is described for intermittent collection of portal venous blood from guinea pigs through a catheter advanced from an ileal tributary of the cranio-mesenteric vein into the portal vein and for the collection of bile from a catheter in the gallbladder after ligature obstruction of the common bile duct.