Effects of substance P (SP) and the N-terminal SP-analogue SP (1-4) on inositol phospholipids in rat adrenal medulla slices.
We previously demonstrated that SP (1.10(-6) M) stimulates the hydrolysis of inositol phospholipids from adrenal medulla slices of Wistar rats (Biomed. Biochim. Acta 46, 461-467 (1987]. In this study we compared the effects of SP and the N-terminal SP-analogue SP(1-4) on inositol phospholipids and their water-soluble metabolites. The effect of SP (1-4) on 32P incorporation into inositol PL is substantially smaller than that of SP. However, the results obtained with [3H]inositol-prelabelled slices show that both peptides cause a diesteratic hydrolysis of inositol phospholipids. For both peptides a significant decrease in [3H]phosphatidylinositol-4,5-bisphosphate as well as an accumulation of [3H]inositol-bisphosphates were observed. There is a significant difference between the effects of SP and SP (1-4): SP stimulates the accumulation of glycerophosphorylinositols, whereas SP (1-4) inhibits its production. These effects of both peptides are discussed in the light of their effects on the catecholamine system.
Minenko
A
A
Institute of Drug Research, Academy of Sciences of the GDR, Berlin.
Tjulkova
E
E
Oehme
P
P
D000313:Adrenal Medulla / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D066298:In Vitro Techniques; D007294:Inositol / Q000378:metabolism; D007295:Inositol Phosphates / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D010446:Peptide Fragments / Q000494:pharmacology*; D010716:Phosphatidylinositols / Q000378:metabolism*; D010743:Phospholipids / Q000378:metabolism; D051381:Rats; D013373:Substance P / Q000494:pharmacology*; D013403:Sugar Phosphates / Q000378:metabolism*
D007295:Inositol Phosphates; D010446:Peptide Fragments; D010716:Phosphatidylinositols; D010743:Phospholipids; D013403:Sugar Phosphates; D013373:Substance P; D007294:Inositol; C042612:substance P (1-4)