title: Attenuation of hypoxic response in cerebral microcirculation following deprenyl.
abstract: Cerebral blood flow (CBF), cerebrocortical microflow (CMF) and local pO2 were measured in the rat brain cortex during normoxia and hypoxic hypoxia before and after administration of the monoamine oxidase-B (MAO-B) inhibitor deprenyl (0.1 mg/100 g b.wt. i.v.). CBF was measured using intraarterial 133-Xenon injection technique. Both, CMF and pO2 were measured using polarographic multiwire surface electrodes. In the control group without deprenyl CBF increased during hypoxaemia (PaO2 = 44.7 +/- 9.3 mm Hg) by 215% while CVR decreased to 27% of the normoxic control value. Hypoxaemia (PaO2 = 34.4 +/- 3.9 mm Hg) also led to a mean increase of CMF by 38% of the normoxic control (p less than 0.02) while the local cerebrocortical pO2 fell from 20.1 +/- 5.1 mm Hg to 5.2 +/- 1.9 mm Hg (p less than 0.02). The administration of deprenyl during normoxia did not cause any significant changes of CBF and CMF although both increased by 29% and 28%, respectively. The increase of CBF during hypoxaemia (PaO2 = 34.9 +/- 6.3 mm Hg) following deprenyl administration, although diminished, was still present (101%, p less than 0.01). CMF decreased under these conditions by 30% on average (p less than 0.05). These results suggest that MAO-B may be involved in the local regulation of cerebrocortical capillary blood flow during hypoxia.
authors.affiliation: Institut für Physiologie und Kardiologie, Universität Erlangen-Nürnberg.
authors.forename: J
authors.initials: J
authors.lastname: Höper
authors.forename: E
authors.initials: E
authors.lastname: Kozniewska
mesh_terms: D000818:Animals; D015687:Cell Hypoxia / Q000187:drug effects*; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D000860:Hypoxia / Q000097:blood; D008297:Male; D008833:Microcirculation; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D051381:Rats; D011919:Rats, Inbred Strains; D012642:Selegiline / Q000494:pharmacology*
chemical_list: D012642:Selegiline; D010100:Oxygen