alpha-melanocyte-stimulating hormone and habituation of prey-catching behavior in the Texas toad, Bufo speciosus. Horm Behav 1999 Aug;36(1):62-9
Date
08/06/1999Pubmed ID
10433887DOI
10.1006/hbeh.1999.1531Scopus ID
2-s2.0-0032837940 (requires institutional sign-in at Scopus site) 12 CitationsAbstract
We investigated dose-dependent effects of alpha-melanocyte-stimulating hormone (alpha-MSH) on habituation in the Texas toad, Bufo speciosus. Additionally, we determined changes in plasma and brain levels of alpha-MSH following peripheral administration of the peptide or following exposure to an ether stressor. The ability of alpha-MSH to facilitate acquisition of habituation was dose dependent. Plasma alpha-MSH concentrations were elevated within 5 min of dorsal lymph sac injection and remained elevated up to 600% over controls after 30 min. Administration of 50 microgram alpha-MSH had no effect on plasma corticosterone levels. Radiolabeled alpha-MSH was detected in cerebrospinal fluid microdialysates within minutes of peripheral injection. Concentrations of alpha-MSH in the telencephalon and preoptic area were significantly lowered after ether exposure, whereas levels in the optic tectum, thalamus/hypothalamus, brainstem, and plasma were unchanged. We conclude that alpha-MSH administered peripherally facilitates habituation in a dose-dependent fashion. Our results confirm that the effects of alpha-MSH are independent of corticosterone secretion. The peptide is cleared rapidly into the bloodstream and enters the cerebrospinal fluid after dorsal lymph sac injection. Neuronal alpha-MSH may help toads gather information about their environment when exposed to certain stressors.
Author List
Olsen CM, Lovering AT, Carr JAAuthor
Christopher M. Olsen PhD Associate Professor in the Pharmacology and Toxicology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsArousal
Brain
Brain Mapping
Bufonidae
Corticosterone
Habituation, Psychophysiologic
Male
Pituitary Gland
Predatory Behavior
Problem Solving
alpha-MSH
