Abstract: The present invention is directed to a series of peptides which may be used for stimulating sexual response in females.

Abstract: Cyclic lactam peptides, seven amino acids in length, having D-2'-naphthylalanine (D-2'-Nal) or D-para-iodo-phenylalanine D-(p-I)Phe at position 4 of the peptide provided potent and specific antagonists of the two neural melanocortin receptors and of the peripheral receptor. In particular, the peptide ##STR1## was found to be a potent antagonist of the MC3 and MC4 receptors with partial agonist activity, and a full agonist of the MC1 and MC5 receptors; the peptide ##STR2## was found to be a potent antagonist of the MC3 and MC4 receptors with partial agonist activity. Both peptides have antagonist activities in the classical frog skin bioassay for pigmentation at the MC1 receptor.

Abstract: Linear and Cyclic Alpha-MSH fragment analogues of Ac-Nle.sup.4 -Glu.sup.5 -His.sup.6 -D-Phe.sup.7 -Arg.sup.8 -Try.sup.9 -Gly.sup.10 -NH.sub.2. The method of stimulating melanocytes by the transdermal application of these biologically-active analogues and compositions comprising these analogues for use in the method are disclosed.

Abstract: A novel class of cyclic bridged analogs of .alpha.-MSH are described herein. With the described analogs, when administered in pharmaceutical compositions, it is now possible to achieve normalization of hypopigmentation dysfunctions and to achieve darkening of the skin in the total absence of sun or UV light irradiation.

Abstract: Cyclic Alpha-MSH fragment analogues of Ac-Nle.sup.4 -Glu.sup.5 -His.sup.6 -D-Phe.sup.7 -Arg.sup.8 -Try.sup.9 -Gly.sup.10 -NH.sub.2. The method of stimulating melanocytes by the transdermal application of these biologically-active analogues and compositions comprising these analogues for use in the method are disclosed.

Abstract: The present invention is directed to a group of linear and cyclic peptides having the structures: ##STR1## These peptides, when systemically administered to animals will bring about a sexual response and are thus useful for the diagnosis and treatment of psychogenic sexual dysfunction in the male.

Abstract: A pharmaceutically active composition comprising a pharmaceutically acceptable carrier and one or more alpha-MSH or analogues thereof for use in the stimulation of integumental melanocytes in vertebrates in order to bring about the production of melanin is disclosed.

Abstract: A method for stimulating integumental melanocytes by the topical application of alpha-MSH analogs, and compositions comprising said analogs for use in the method are described.

Abstract: A method for stimulating integumental melanocytes by the topical application of alpha-MSH analogs, and compositions comprising said analogs for use in the method are described.

Abstract: Cyclic analogues of the tridecapeptide hormone, .alpha.-melanotropin. (.alpha.-melanocyte stimulating hormone, .alpha.-MSH), wherein a physiologically stable intramolecular interaction exists (1) between the amino acid residue at position 4 and an amino acid residue at position 10 or 11, and/or (2) between the amino acid residue at position 5 and an amino acid residue at position 10 or 11. Preferred analogues, e.g., [half-Cys.sup.4, half-Cys.sup.10 ]-.alpha.-MSH display greatly increased in vitro potency, prolongation, and resistance to enzymatic degradation.

Abstract: Analogues of the tridecapeptide hormone, .alpha.-melanotropin (a-melanocyte stimulating hormone, .alpha.-MSH) of the formula:Ac-Ser.sup.1 -Tyr.sup.2 -Ser.sup.3 -Y.sup.4 -Glu.sup.5 -His.sup.6 -X.sup.7 -Arg.sup.8 -Trp.sup.9 -Gly.sup.10 -Lys.sup.11 -Pro.sup.12 -Val.sup.13 -NH.sub.2wherein X and Y are amino acid residues and X is in a D-isomeric configuration. Preferred analogues, e.g. [Nle.sup.4, D-Phe.sup.7 ]-.alpha.-MSH, display increased in vitro and in vivo potency, prolongation and serum stability characteristics and may be covalently bonded to other elements or compounds (e.g., radioisotopes of iodine) without significant loss of biological activity.