[Changes in the efficacy of vasoconstrictor stimuli in acute and chronic hypotension in the microcirculatory bed of rat skeletal muscle].
Microvascular diameters in m. extensor hallucis proprius of rats were measured by the image split method. The baseline diameters and responses to the electrical stimulation (20 Hz, 10 s) of the sympathetic tract were obtained in arterioles i. d. 7.8-88 microns. Measurements were made under baseline pressure into the right femoral artery, 1 min after local blood pressure drop (LBPD) produced by inflation of the cuff around descending aorta and in the rats with the chronic (1-2 months) regional hypotension (CRH) produced by implantation of a metal coil narrowing the aorta. Thirty five arterioles out of 45 showed reduction of responsiveness to sympathetic stimulation after LBPD (mean-19.1 +/- 2.1%), 6 arterioles reacted by insignificant enhancing of the constrictor responses and the reactions of 3 vessels were more pronounced (mean-21.1 +/- 9.1%). The responsiveness to sympathetic stimulation of the skeletal muscle arterioles i. d. 10-20 microns exposed to CRH did not differ from that in the sham-operated rats (11.6 +/- 1.3% vs 10.4 +/- 0.1%).
Timkina
M I
MI
Shenderov
S M
SM
D000208:Acute Disease; D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D002908:Chronic Disease; D004558:Electric Stimulation; D005263:Femoral Artery / Q000503:physiopathology; D007022:Hypotension / Q000503:physiopathology*; D008297:Male; D008833:Microcirculation / Q000503:physiopathology; D009132:Muscles / Q000098:blood supply*; D051381:Rats; D013564:Sympathetic Nervous System / Q000502:physiology; D014661:Vasoconstriction / Q000502:physiology*
Izmeneniia v éffektivnosti vazokonstriktornykh stimulov pri ostroĭ i khronicheskoĭ gipotenzii v mikrotsirkuliatornom rusle skeletnoĭ myshtsy krysy.