Janse C, Wildering W C, Popelier C M
Department of Biology, Vrije Universiteit, The Netherlands.
J Gerontol. 1989 Nov;44(6):B148-55. doi: 10.1093/geronj/44.6.b148.
Age-related changes in reproduction and growth of the pulmonate snail Lymnaea stagnalis were studied in animals under standard culture conditions. Longitudinal studies as well as cross-sectional studies were done. Egg-laying activity starts in Lymnaea at an age of about 2 months. Up to an age of about 250 days it increases, and in older snails it decreases with age. Cross-sectional studies showed that the increase in egg-laying activity is due to an increase in the number of animals that lay eggs and to an increase in the egg-laying frequency of individuals. The decrease in egg-laying activity is due to a decrease in the egg-laying frequency of individual animals and to an increase in the number of animals that stop egg laying. Growth (shell length and body weight) ceases at about the same age at which egg laying begins to decrease. The results are discussed in relation to the organization of the neuroendocrine system in Lymnaea and to results of earlier studies on age-related changes in peptidergic neurons in the CNS of Lymnaea.
在标准培养条件下，对椎实螺（Lymnaea stagnalis）繁殖和生长的年龄相关变化进行了研究。进行了纵向研究和横断面研究。椎实螺约2个月大时开始产卵活动。在约250日龄之前产卵活动增加，而在年龄较大的蜗牛中，产卵活动随年龄增长而下降。横断面研究表明，产卵活动的增加是由于产卵动物数量的增加以及个体产卵频率的提高。产卵活动的下降是由于单个动物产卵频率的降低以及停止产卵动物数量的增加。生长（壳长和体重）在产卵开始下降的大致相同年龄停止。结合椎实螺神经内分泌系统的组织以及早期关于椎实螺中枢神经系统中肽能神经元年龄相关变化的研究结果对这些结果进行了讨论。
