ISSN:
1432-0878
Keywords:
Reproductive tract
;
Biomphalaria glabrata
;
Desiccation
;
Starvation metabolism
;
Weighing experiments
;
Histochemistry
;
Electron microscopy
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary The effects of desiccation (36 weeks), starvation (12 weeks) and recovery (4 weeks following 16 weeks of desiccation and 2 weeks following 9 weeks of starvation) upon the accessory sex glands and some other body parts of Biomphalaria glabrata were studied by means of weighing experiments and histochemical and ultrastructural methods. The results of the weighing experiments show that the various parts of the reproductive tract are not protected from involution processes during the adverse conditions, as some parts (the albumen gland, spermduct and prostate gland) showed a more pronounced decrease in weight than other body parts. Measurements of the epithelial heights of the accessory sex glands and ultrastructural observations corroborate the results of the weighing experiments. During the adverse conditions the organelles involved in the formation of the secretion granules (granular endoplasmic reticulum and Golgi-apparatus) became involuted. The secretion granules within the cells of the albumen gland, spermduct and prostate gland were broken down by crinophagy. This latter process was less pronounced in the oviduct, muciparous gland, oöthecal gland, uterus and vagina. During the adverse conditions the lipoprotein producing cell types (mainly in the male part) remained active longer than the polysaccharide producing cell types (mainly in the female part). The significance of this observation is discussed. The amounts of glycogen present in most tissues of the reproductive tract and of the other investigated body parts (the foot, columellar muscle and vesicular connective tissue cells) were not apparently diminished, even when the secretory cells showed clear signs of involution, as a result of long periods of adverse conditions. Within the recovery periods 50% of the snails resumed egg production. During recovery the relative increases in weight of the accessory sex glands seemed to exceed that of other body parts, indicating that the restoration of the accessory sex glands is favoured. Histologically, reactivation of the accessory sex glands was apparent after 36–72 hours of recovery. At this time secretory material was again observed within the cisternae of the gland cell Golgi-bodies. Because reactivation is fairly rapid, a nervous or hormonal control of this process appears more likely than control via the general metabolism. The possible functions of various body organs in storing food reserve material is discussed, and it is concluded that the glycogen storing vesicular connective tissue cells (which occur throughout the whole body in the connective tissue) play a major role.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00307443
