A. Spreca et Mg. Rambotti, ULTRACYTOCHEMICAL LOCALIZATION OF PARTICULATE GUANYLATE-CYCLASE AFTERSTIMULATION WITH NATRIURETIC PEPTIDES IN LAMB OLFACTORY MUCOSA, Histochemical Journal, 26(10), 1994, pp. 778-786
The ultracytochemical localization of particulate guanylate cyclase ha
s been studied in lamb olfactory mucosa after activation with rat atri
al natriuretic factor (rANF), porcine brain natriuretic peptide (pBNP)
, porcine C-type natriuretic peptide (pCNP) or rat brain natriuretic p
eptide (rBNP). Particulate guanylate cyclase is the receptor for these
peptides and recently two subtypes of the cyclase have been identifie
d. These isoforms are stimulated differently by ANF, BNP and CNP. Unde
r our experimental conditions, rANF, pCNP and pBNP were strong activat
ors of particulate guanylate cyclase in lamb olfactory mucosa, as demo
nstrated by the presence of reaction product. Samples incubated in bas
al conditions without rANF, pCNP or pBNP, or samples incubated in pres
ence of rBNP did not reveal any cyclase activity. The rANF-stimulated
cyclase activity was localized in the apical portion of olfactory epit
helium. pCNP-stimulated guanylate cyclase was detected to the lamina p
ropria in association with secretory cells of Bowman's glands and with
cells in close relation with Bowman's glands (elongated cells and myo
epithelial cells). The cyclase activity stimulated by pBNP was limited
to cells of Bowman's glands. The present data indicate that ANF and C
NP are recognized by different receptors and that BNP and CNP bind to
the same receptor.