成年雌性比格犬发情期中生殖激素变化规律

Levels of Plasma Reproductive Hormones in Oestrus Beagle Bitches

研究成年雌性比格犬体内促黄体生成激素(LH)、雌二醇(E2)及孕酮(P)的分泌规律。采用放射免疫法测定母犬发情期内血清中LH、E2及P的含量。所有10只成年雌性比格犬LH浓度在发情前期开始后8～11d达到最高浓度7.41±0.48mU/mL。E2浓度在发情前期开始后的7～11d达到最高值80.64±5.73pg/mL,有8只成年雌性比格犬E2的峰值出现在LH峰值前24h,之后迅速下降,同时P浓度开始初次升高,并维持在这一浓度(14.16±2.52ng/mL)3～5d之后继续升高,P在LH峰值后的10～14d达到最高值36.19±2.04ng/mL。实验表明E2对LH峰值的出现具有负反馈调节作用,E2∶P浓度比的下降促使LH峰值出现。

Plasma luteinizing hormone（LH）,estradiol（E2） and proestrus in oestrus Beagle Bitches Canine were determined by the method of radioimmunoassay（RIA） to clarify the tendency of the reproductive hormones when Canine is in estrus cycle.The results showed that Plasma LH reaches the peak level（7.41± 0.48） mU/mL during 8~11 d after proestrus in ten bitches.Estradiol gets to the peak level（80.64±5.73）pg/mL during the 7~11 d after the starting of proestrus.The highest concentration of plasma estradiol（80.64±5.73） pg/mL occurrs at 24 h before the LH peak in eight bitches,then begin to decrease sharply,meanwhile progesterone begin to initially arise and remains this level（14.16 ± 2.52） ng/mL 3~5 d,then reaches peak concentration（36.19 ± 2.04） ng/mL during 10~14 d after LH peak.It can be concluded that estradiol has a negative feedback on LH secretion,and the peak level of LH is involved in the decrease of E2∶P ratio.