Studies on histamine hypotension

Central histamine-induced reversal of critical haemorrhagic hypotension in rats--haemodynamic studies.

Volume-controlled irreversible haemorrhagic shock in rats produced by blood withdrawal until stabilisation of critical mean arterial pressure (MAP) 20-25 mmHg is associated with an extreme decrease in cardiac index (CI) and an increase in total peripheral resistance index (TPRI), with reductions in renal (RBF), hindquarters (HBF) and mesenteric blood flow (MBF), and leads to the death of all co...

Studies on histamine-metabolizing enzymes in intact animals. II.

Studies on activation of H3 histamine receptor: a mechanistic model.

The recognition and the activation mechanism of the H3 histamine receptor was studied based on quantum-chemical calculations. A mechanistic model proposed both for recognition and activation stage clarifies different properties of histamine and alpha-methylhistamine at the H3 receptor. Interaction with a hypothetical receptor sites leads to the opening of the intramolecular hydrogen bonding in ...

In vivo studies on histamine catabolism and its inhibition.

1. Histamine catabolism in vivo was studied in mice subjected to various forms of pretreatment; tissues from mice killed 2.5 min after intravenous injection of (14)C-histamine were assayed for (14)C-histamine, (14)C-methylhistamine and total (14)C.2. Pretreatment of mice with aminoguanidine, an inhibitor of diamine oxidase, strongly increased levels of (14)C-histamine in intestine; pretreatment...

Studies in Clinical Shock and Hypotension

a rapid infusion of dextran. Cardiac output returned to normal in 20 patients and shock or hypotension was corrected in 16. In 10 patients with evidence of vasoconstriction and normal cardiac function, dextran reversed the circulatory abnormality, returning blood pressure, cardiac output, and peripheral vascular resistance to normal. Twelve patients with hypotension without evidence of reflex v...