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J L Haining

Publications and source records attributed to J L Haining.

24 records · Page 2Linked to original sources
PubMedDate not supplied

Measurement of local skeletal muscle blood flow in animals by the hydrogen electrode technique.

The hydrogen (H2) electrode technique has been applied to the measurement of local skeletal muscle blood flow (LSMBF) in experimental animals (rats, rabbits, and monkeys). LSMBF was measured during resting and postexercise states, following epinephrine injections and during CO2 inhalation. Among the limited sites studied and/or measurements obtained, significant differences in LSMBF were found in only a few instances. During hypercapnia, LSMBF was found to be increased in some muscles in rats and monkeys. The present study demonstrates that the H2 electrode technique is a simple and reliable method for measuring resting and postexercise LSMBF in anesthetized animals. This method provides measurements at discrete loci, is easily reproducible, and causes little trauma.

Animals↗
PubMedDate not supplied

Measurement of local skeletal muscle blood flow in normal humans by hydrogen clearance.

The hydrogen (H2) electrode technique was adapted to the measurement of local skeletal muscle blood flow (LSMBF) in humans. Thirty-five normal volunteers were utilized to study the biceps, deltoid, gastrocnemius, and quadriceps muscles at rest and following exercise. Results indicated statistically significant increases (P < 0.05) in postexercise compared with resting blood flows within the muscles. The highest mean value for LSMBF was found in deltoid muscle and the lowest in biceps. This study demonstrates the potential superiority of the H2 electrode technique over previous techniques for measuring absolute muscle blood flow at individual sites. It is suggested that measurements by means of the H2 electrode technique represent the most definitive values for skeletal muscle blood flow at this time, and its application could be especially important in various neuromuscular disorders in which some question remains concerning the role of abnormalities of the skeletal muscle vasculature.

Adult↗
PubMedDate not supplied

Constrictive endarteropathy following experimental subarachnoid hemorrhage.

Rhesus monkeys were subjected to subarachnoid hemorrhage by either the introduction of blood into the subarachnoid space or by mechanically rupturing the middle cerebral artery. Local cerebral blood flow, vascular compliance studies, and histological studies (light and electron microscope) were made of the vessels of all animals. In animals hemorrhaged via vascular rupture, subintimal swelling and thickening was minimally present by 3 days, becoming progressively more severe by one month. Such changes consisted of severe subintimal proliferation, fibrosis of the medial smooth muscle layer and interruption of the internal elastic membrane. Cells in the subintimal proliferative areas examined by electronmicroscopy were seen to have ultrastructural characteristics of smooth muscle. In the subarachnoid-injected hemorrhaged animals, there was no evidence of intimal proliferation or other vascular changes, which was also true of all control vessels. There was a decrease in wall elasticity of vessels exposed to mechanical rupture when compared to those exposed only to injected subarachnoid blood or normal vessels. Local cerebral blood flow was affected very little following the 2 methods of subarachnoid hemorrhage.

Animals↗