Title

Short term neonatal starvation altered cholera toxin binding in rabbits

UMMS Affiliation

University of Massachusetts Medical Center

Publication Date

2-1-1989

Document Type

Article

Subjects

Adenylate Cyclase; Animals; Animals, Newborn; Cholera Toxin; Food; *G(M1) Ganglioside; Intestinal Mucosa; Microvilli; Rabbits; *Receptors, Cell Surface; Receptors, Immunologic; Starvation; Time Factors

Disciplines

Life Sciences | Medicine and Health Sciences

Abstract

Acute neonatal malnutrition alters lumenal glycoproteins as demonstrated by altered lectin binding. To determine the effect of a 72-h fast on lumenal glycolipids, specifically the monosialoganglioside GM1, we quantitated cholera toxin (CT) binding and adenylate cyclase activity. The calculated number of specific sites for CT binding to microvillus membrane (MVM) from newborn rabbits fasted for 72 h was decreased in MVM from proximal small bowel (7 +/- 0.8 x 10(8)/micrograms protein) compared to 72-h control neonatal rabbits (18 +/- 3.3 x 10(8) micrograms protein). In distal small bowel there was no difference in the calculated receptor sites/micrograms MVM protein between fasted (8 +/- 1.7 x 10(8)) and fed (11 +/- 4 x 10(8)) groups. MVM prepared from proximal small bowel of fed animals bound significantly more CT than MVM prepared from distal small bowel of fed animals. The affinity for CT was the same in all MVM preparations. Neuraminidase treatment of MVM resulted in increased CT binding in fed and fasted rabbit proximal and distal MVM preparations, but the greatest increase occurred in MVM prepared from proximal small bowel from fasted animals. There was no difference in adenylate cyclase activity in fed, fasted, and proximal or distal small bowel crude membrane preparations. Refeeding (120 h) resulted in normalization of CT binding in MVM from proximal small bowel of fasted animals. We conclude a 72-h fast in neonatal rabbits resulted in decreased regional CT binding in MVM prepared from proximal small bowel of fasted animals, but no change in adenylate cyclase activity. Refeeding reverses CT binding abnormalities.

Rights and Permissions

Citation: J Nutr. 1989 Feb;119(2):280-5.

Related Resources

Link to Article in PubMed

Journal/Book/Conference Title

The Journal of nutrition

PubMed ID

2918402