Abstract: The invention provides synthetic peptides which are extremely potent in stimulating the release of pituitary GH in mammals and which have the formula: H-Tyr-Ala-Asp-Ala-Ile-Phe-Thr-Asn-Ser-Tyr-Arg-Lys-Val-Leu-Gly-Gln-Leu-Ser- Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Met-Ser-Arg-Gln-Gln-Gly-Glu-Arg-Asn-Gln-Glu -Gln-Gly-Ala-Arg-Val-Arg-Leu-Y wherein Y is OH or NH.sub.2. These peptides or biologically active fragments thereof, or analogs thereof having well-known substitutions and, or additions, as well as nontoxic salts of any of the foregoing, may be administered therapeutically to mammals, including humans, and may be used diagnostically. The peptides are useful in stimulating the release of GH and accelerating growth in warm-blooded non-human animals, particularly pigs, and in improving aquiculture.

Abstract: The invention provides synthetic peptides which are extremely potent in stimulating the release of pituitary GH in mammals and which have the formula: H-Tyr-Ala-Asp-Ala-Ile-Phe-Thr-Asn-Ser-Tyr-Arg-Lys-Val-Leu-Gly-Gln-Leu-Ser- Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Met-Asn-Arg-Gln-Gln-Gly-Glu-Arg-Asn-Gln-Glu -Gln-Gly-Ala-Lys-Val-Arg-Leu-Y wherein Y is OH or NH.sub.2. These peptides or biologically active fragments thereof, or analogs thereof having well-known substitutions and/or additions, as well as nontoxic salts of any of the foregoing, may be administered therapeutically to mammals, including humans, and may be used diagnostically. The peptides are useful in stimulating the release of GH so as to accelerate growth in warm-blooded non-human animals, particularly cattle, and/or to increase the production of milk in lactating cows, and also in improving aquiculture.

Abstract: PGRF has been synthesized. The invention provides synthetic peptides which are extremely potent in stimulating the release of pituitary GH in mammals and which have the formula: ##STR1## wherein R is OH or NH.sub.2, R.sub.34 is Ser or Ala, R.sub.38 is Arg or Ser, R.sub.40 is Ala or Arg and R.sub.41 is Arg, Arg-Ala, Arg-Ala-Arg, Arg-Ala-Arg-Leu or des-R.sub.41. These peptides or biologically active fragments thereof, or analogs thereof having well-known substitutions and/or additions, as well as nontoxic salts of any of the foregoing, may be administered therapeutically to mammals, including humans, and may be used diagnostically.

Abstract: 28-member residue and 25-member residue peptides have been synthesized containing the tetradecapeptide somatostatin that are more potent than somatostatin. Somatostatin-28 has the formula: ##STR1## The three N-terminal amino acid residues are absent in somatostatin-25. Somatostatin-28 or somatostatin-25 or a pharmaceutically acceptable addition salt thereof, dispersed in a pharmaceutically acceptable liquid or solid carrier, can be administered to mammals in the same manner as somatostatin.

Abstract: Somatostatin (SS) is modified to incorporate a carbohydrate moiety in the peptide chain by linkage to either Asn, Ser or Thr. The modified SS peptide analog may have the formula: ##STR1## wherein R.sub.1 is preferably a hexose or amino-hexose, such as glucose or N-acetylglucosamine. Alternatively, the carbohydrate can be linked to Ser or Thr by an ether bond. Such glycosomatostatins have an extended biological half-life compared to the parent peptide and substantially the same potency. Modifications and substitutions with respect to other amino acid residues in the chain can be made in the glycopeptides, for the purpose of increasing the effectiveness of SS analogs in other ways, and such increased effectiveness is a characteristic of the glycosomatostatin along with its longer-acting biological effect.