The Effects of Sympathetic Nerve Stimulation on the Tracer Disappearance Rate and Local Blood Content in the Nasal Mucosa of the Cat

Abstract

The effects of sympathetic nerve activation j on tracer disappearance rate and local blood content J in the cat nasal mucosa were studied by measuring local disappearance of ¹²⁵I⁻ and changes in gross pulse rate from ¹³¹I-labelled serum albumin monitored over i the nose. Major changes in the tracer disappearance rate were seen in the frequency range of 0.5-6.0 imp/sec while similar changes in the local blood content occurred at 0.1-0.5 imp/sec, indicating a functional differentiation in the vasoconstrictor control of (the exchange and capacitance vessels during low sympathetic tone. The observed responses were shown to ' be due to activation of sympathetic adrenergic nerves and receptors of the a-type. No evidence of vasodilator influence due to stimulation of β-receptors or sympathetic cholinergic vasodilator fibers was found 1