Sympathetic neurotransmission in the rabbit isolated central ear artery is affected as early as one week following a single dose of X-irradiation

TY - JOUR

T1 - Sympathetic neurotransmission in the rabbit isolated central ear artery is affected as early as one week following a single dose of X-irradiation

AU - Stewart-Lee, A. L.

AU - Maynard, K. I.

AU - Lincoln, J.

AU - Burnstock, G.

PY - 1991/1

Y1 - 1991/1

N2 - 1 The short-term effect of a single dose of 4500 rad X-irradiation on sympathetic neurotransmission (involving both noradrenergic and purinergic components) was assessed in the rabbit central ear artery, 1, 4 and 6 weeks post-irradiation. 2 Neurally mediated contractions were reduced as early as 1 week post-irradiation, with responses to lower frequency stimulation being initially most affected. This suggests that the purinergic component of the contractile response is affected earlier than the adrenergic component. 3 There was no change in the amplitude or sensitivity of treated preparations to the cumulative application of noradrenaline when compared with untreated preparations. In contrast, contractions to α,β-methylene ATP (1 μM), a P2-purinoceptor agonist, were significantly increased at 4 and 6 weeks post-irradiation, although not at 1 week post-irradiation. 4 There were no apparent changes in the pattern of catecholamine fluorescence as a result of irradiation. However, the tissue content of noradrenaline was significantly reduced 6 weeks post-irradiation when compared with control preparations. 5 It is concluded that damage to sympathetic cotransmission is one of the early effects of irradiation, with initial impairment predominantly of the purinergic component.

AB - 1 The short-term effect of a single dose of 4500 rad X-irradiation on sympathetic neurotransmission (involving both noradrenergic and purinergic components) was assessed in the rabbit central ear artery, 1, 4 and 6 weeks post-irradiation. 2 Neurally mediated contractions were reduced as early as 1 week post-irradiation, with responses to lower frequency stimulation being initially most affected. This suggests that the purinergic component of the contractile response is affected earlier than the adrenergic component. 3 There was no change in the amplitude or sensitivity of treated preparations to the cumulative application of noradrenaline when compared with untreated preparations. In contrast, contractions to α,β-methylene ATP (1 μM), a P2-purinoceptor agonist, were significantly increased at 4 and 6 weeks post-irradiation, although not at 1 week post-irradiation. 4 There were no apparent changes in the pattern of catecholamine fluorescence as a result of irradiation. However, the tissue content of noradrenaline was significantly reduced 6 weeks post-irradiation when compared with control preparations. 5 It is concluded that damage to sympathetic cotransmission is one of the early effects of irradiation, with initial impairment predominantly of the purinergic component.

U2 - 10.1111/j.1476-5381.1991.tb12126.x

DO - 10.1111/j.1476-5381.1991.tb12126.x

M3 - Article

C2 - 1646058

AN - SCOPUS:0025845461

SN - 0007-1188

VL - 102

SP - 23

EP - 26

JO - British journal of pharmacology

JF - British journal of pharmacology

IS - 1

ER -