Uptake1, uptake2 and the release of [3H]-noradrenaline in uterine artery of pigs during the oestrous cycle.

Abstract

Neuronal uptake (uptake1), extraneuronal uptake (uptake2) and the spontaneous release of 2H-noradrenaline (NA) in uterine artery of swine on days 0, 1-2, 13-14 and 16-18 of the oestrous cycle were studied. It was found that uptake1 was lowest on the day of ovulation (day 0) and then it increased by 37.4% (p < 0.05) and by 93.7% (p < 0.01) on days 1-2 and 13-14, respectively. On days 16-18 of the oestrous cycle uptake1 was insignificantly higher (9.3%) compared to the day 0. Also uptake2 was the lowest on day 0 and next it increased to 180.1% (p < 0.01) on days 1-2. Thereafter this value was still higher compared to day 0 but it had decreasing tendency: 140.3% (p < 0.05) on days 13-14 and 113.8% on days 16-18 of the oestrous cycle. Release of neuronal radioactivity was the lowest on day 0 and then it increased by 40.0-44.2% (p < 0.05), 46.8-49.5% (p < 0.05) and 26.1-28.1% (p > 0.05) on days 1-2, 13-14 and 16-18 of the oestrous cycle, respectively. The release of extraneuronal radioactivity was the highest on day 0 (accepted as 100%) and similarly high (88.6-91.8%) on days 13-14 but markedly lower (28.3-36.0%; p < 0.05) on days 1-2 and 16-18 (43.9-50.1%; p < 0.05) compared to the value on day 0 of the oestrous cycle.