Evidence for a stimulating effect of prolactin on teleostean hatching enzyme secretion

✍ Scribed by Schoots, André F. M. ;de Bont, Rob G. ;Van Eys, Guillaume J. J. M. ;Denucé, J. Manuel

• Book ID: 102336919
• Publisher: John Wiley and Sons
• Year: 1982
• Tongue: English
• Weight: 339 KB
• Volume: 219
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1402190118

✦ Synopsis

Abstract

Homogenates of whole medakas and of trout prolactin lobes contain a factor that stimulates hatching enzyme secretion from medaka hatching gland explants. The elution volume in gel filtration indicates that the stimulating factor is a protein with a molecular weight of 19,000–20,000. Both its localization in the prolactin lobe and its apparent molecular weight suggest that this factor is prolactin. This is confirmed by an electrophoretic analysis of the biomajor products of the prolactin lobe, which demonstrates that prolactin is the major product found in the molecular mass range from 15,000 to 30,000 daltons. Since it is known that the pituitary gland of teleostean embryos has functional prolactin cells and that prolactin is an activator of integumentary glandular cells, we conclude that prolactin might be the primary stimulus in the activation of hatching gland cells leading to hatching enzyme secretion.