Bóveda Gómez Paula, Velázquez Rosario, Martínez-Fresneda Lucía, Mejía Octavio, Oteo Marta, Toledano-Díaz Adolfo, Castaño Cristina, Esteso Milagros Cristina, Ungerfeld Rodolfo, López-Sebastián Antonio, Santiago-Moreno Julian
Department of Animal Reproduction, INIA-CSIC, Madrid, Spain.
Centro de Enseñanza, Investigación y Extensión en Producción Ovina, FMVZ-UNAM, Morelos, México.
Biopreserv Biobank. 2023 Apr;21(2):142-148. doi: 10.1089/bio.2021.0129. Epub 2022 Jun 8.
This work examined the influence of induced changes in prolactin (PRL) secretion on sperm cryoresistance of ibex and the mouflon. PRL secretion was modified in a first experiment by the use of bromocriptine (BCR, dopamine agonist) during the non-breeding season, and in a second experiment by the use of sulpiride (SLP, dopamine D-receptor antagonist) during the rutting season. Slow and ultra-rapid freezing protocols were used to cryopreserve sperm samples. BCR decreased blood plasma PRL concentrations, whereas SLP increased them. Cryoresistance ratios (CRs) for curvilinear velocity (VCL), straight-line velocity (VSL), and average path velocity (VAP) in BCR-treated mouflons were lower than in controls using slow-freezing ( < 0.05), while CRs of motility and morphologically normal sperm of BCR-treated mouflons were greater than controls with ultra-rapid freezing ( < 0.05). BCR increased the head sperm dimensions in ibexes ( < 0.001); conversely, BCR decreased the head dimensions in mouflons ( < 0.001). CR-motility, CR-amplitude of lateral head displacement (ALH), CR-viability, and CR-acrosome integrity in SLP-treated mouflons were lower than in controls with slow-freezing ( < 0.01); CR-viability and CR-acrosome were lower than controls with ultra-rapid freezing ( < 0.05). In ibexes, CR-ALH was lower for SLP-treated ( < 0.05). SLP treatment increased head dimensions in ibexes ( < 0.001) but did not affect the sperm head of mouflons. Our findings show that high levels of blood plasma PRL negatively affect the cryoresistance of ibex and mouflon sperm.
本研究考察了催乳素（PRL）分泌的诱导变化对羱羊和摩弗伦羊精子冷冻抗性的影响。在第一个实验中，于非繁殖季节使用溴隐亭（BCR，多巴胺激动剂）改变PRL分泌；在第二个实验中，于发情季节使用舒必利（SLP，多巴胺D受体拮抗剂）改变PRL分泌。采用慢速和超快速冷冻方案对精子样本进行冷冻保存。BCR降低了血浆PRL浓度，而SLP则提高了血浆PRL浓度。BCR处理的摩弗伦羊中，曲线速度（VCL）、直线速度（VSL）和平均路径速度（VAP）的冷冻抗性比率（CRs）低于慢速冷冻的对照组（<0.05），而BCR处理的摩弗伦羊中，活力和形态正常精子的CRs高于超快速冷冻的对照组（<0.05）。BCR增加了羱羊精子头部尺寸（<0.001）；相反，BCR减小了摩弗伦羊精子头部尺寸（<0.001）。SLP处理的摩弗伦羊中，CR-活力、CR-头部横向位移幅度（ALH）、CR-存活率和CR-顶体完整性低于慢速冷冻的对照组（<0.01）；CR-存活率和CR-顶体完整性低于超快速冷冻的对照组（<0.05）。在羱羊中，SLP处理的CR-ALH较低（<0.05）。SLP处理增加了羱羊精子头部尺寸（<0.001），但对摩弗伦羊精子头部无影响。我们的研究结果表明，高水平的血浆PRL对羱羊和摩弗伦羊精子的冷冻抗性有负面影响。
