A basic rhythmicity in the mitotic rate of urodele epidermis and the difference in mitotic rate between larvae reared in the laboratory and in a pond

✍ Scribed by Scheving, Lawrence E. ;Chiakulas, John J. ;Abzug, Hillyard I.

• Publisher: Wiley (John Wiley & Sons)
• Year: 1959
• Tongue: English
• Weight: 443 KB
• Volume: 54
• Category: Article
• ISSN: 0095-9898
• DOI: 10.1002/jcp.1030540112

✦ Synopsis

Periodic rhythms have been described for a number of physiological processes in both plants and animals. The phenomenon of periodicity in the rate of cell division was first reported by Fortuyn-van Leyden ('17, '26) who established definite rhythms in mitotic activity in a number of cat tissues. Similar results have been reported by Ortiz-Pic6n ('34), Carleton ('34), Cooper and Franklin ('40) and Bullough ('48) on mouse epidermis; by Blumenfeld ('39), Babick ('51) and Halberg et al. ('54) on rat epidermis; by Cooper and Schiff ('38), Broders and Dublin ('39) in human infant prepuce and by Scheving and Gatz ('55) in adult human epidermis. In amphibian tissues, Mollerberg ('48) reported this same cyclic phenomenon in the epidermis, and Meyer ('54) in the cornea of frog larvae.

Salamander epidermis has been used extensively as a convenient "test tissue" in many studies of the mitotic process. These studies include the effects of underlying grafts, starvation and feeding, etc. on mitotic stimulation or inhibition (Overton, '50, '57). Numerous investigations have been made of the mitotic phenomena associated with epidermal wound healing and regeneration (Lash, '55; Weber, '57). Investigations of this type have dealt with mitotic indices, but usually with little or no consideration of a rhythmic or cyclic manifestation of the normal mitotic process. For instance, DiBerardino ('55), reporting on mitotic frequency in the epidermis of normal and regenerating tail tips of frog larvae, makes no mention of the time of day when tissues were obtained for the study.