Respiration and Blood Circulation of Fish.

The Control of Respiration and Circulation in Fish during Exercise and Hypoxia

Gas exchange across fish gills is reviewed and the respiratory and cardiovascular changes associated with exercise and hypoxia described. Heart rate is controlled by inhibitory vagal cholinergic activity which increases during hypoxia and decreases during exercise. Stimulation of receptors on the first gill arch during hypoxia initiates bradycardia. The increase in stroke volume during hypoxia ...

Collected Papers on Circulation and Respiration

A Study of the Circulation, Blood Pressure, and Respiration of Sharks

The average branchial blood pressure in sand sharks was 32 mm. of mercury. The highest recorded in a resting animal was 43 mm. The average dorsal or systemic pressure was 23.3 mm.; highest 30 mm. The ratio of branchial to systemic pressure is about 3 to 2. The pressure in both systems keeps up well under trauma; but under experimental conditions, with or without manipulation of viscera, slowly ...

Excretion of Acebutolol and its Major Metabolite Diacetolol into Infant Blood Circulation and the Breast Milk

Acebutolol (AC) is a chiral b-adrenergic blocking drug, which is useful clinically as the racemate in treating hypertension and is metabolized to an equipotent chiral metabolite, diacetolol (DC). In this paper we report a case of a 32 year old woman who was receiving AC during her pregnancy and lactating time for management of hypertension. The maternal plasma level and breast milk as well as c...

Control and co-ordination of respiration and circulation.