Pharmacological Research, Vol. 26, Supplement 1, 1992 231

INTERACTIONS BETWEEN PROLACTIN AND INFLAMMATORY PROCESSES

Meli R., Gualillo O., Mattace Raso G., Di Carlo R. Department of Experimental Pharmacology, University of Naples Federico II

The pro-inflammatory activity of prolactin has been established using different experimental models of inflammation: carrageenin or phospholipase A2-induced paw oedema, carrageenin-induced pleurisy, adjuvant arthritis and cotton pellet induced granuloma. Repeated administrations of ovine PRL or in some instances a hyperprolactinaemia induced by pituitary gland graft always provoked an evident increase of the inflammatory responses, whereas a hypoprolactinaemia induced by administration of bromocriptine markedly reduced the inflammation. The observed activity of PRL is in good agreement with the well-established immunoregulatory role of PRL (11, in view of the correlation existing between inflammatory and immune reactions.

1. Di Carlo R and Meli R Acta Neurologica 1991; 13: 380-385

CHANGES OF CEREBROSPINAL FLUID PROTEINS IN THE RAT DURING ACUTE INFLAMMATION

Saso L1, Silvestrini B1, Zwain IH2, MO MY2, Li AHY2, and Cheng CY2. IInstitute of Pharmacology and Pharmacognosy, “La Sapienza” University, P.le Aldo Moro 5, 00185 Rome, Italy; and 2The Population Council, 1230 York Avenue, New York, NY 10021, USA.

Acute inflammation in the rat is accompanied by a drastic increase in the levels of alpha-2- macroglobulin (alpha-2-M) and hemopexin (HM) in the systemic circulation. However, no increase in the level of alpha-2-M was detected in the testis behind the blood-testis barrier. We thus sought to determine if acute inflammation induces any changes on the levels of these proteins in cerebrospinal fluid (CSF) behind the blood-brain barrier. Adult rats were sacrificed at 6, 24, and 48 hr following induced inflammation. The levels of alpha-2-M and HM in the serum and CSF were quantified by RIA or immunoblots and compared to control rats. The changes of the alpha-2-M mRNA in the brain, liver, and testis were also examined by Northern blots. It was noted that alpha-2-M increased by more than loo-fold in the serum but only by 2- fold in the CSF whereas HM increased by about lo-fold in the CSF during acute inflammation. The alpha-2-M mRNA increased significantly in the liver but to a lesser extent in the brain during acute inflammation; however, its mRNA level did not change in the testis during inflammation. These results suggest that there has a differential regulatory mechanism in the expression and secretion of these proteins in different compartments in inflammatory conditions.