Effects of cocaine on vascular ADP-ase activity

Pharmacological

77

Research, 61. 26, Supplement I, 1992

ETRANOLINDUCEDVARIATIONS ON GLUTATHIONELEVELS IN RAT MJSCLE Anna Ida Fiaschi, Micheli, Raffaella Romeo, Lucia Cerretani, Giorgio Giorgi. Maria

Institute

of Pharmacology,

University

of Siena,

Several studies demonstrated that chronic causes structural change to hepatic cells alterations. In the present research we intraperitoneal EtOH (3 ml/Kg) administration leg of rats. Male albino Wistar rats, not receiving a standard diet were, used. The for GSH levels of at least 5 animals parenthesis s.d.).

Daniela

Italy.

ethanol (EtOH) administration and also important biochemical studied the effect of oral or on GSH levels of the right fasted, (average weight 200 g) table show the average values as percent of controls (in

Time (hours) Control

1

OS

100 (16.0)

109 (13.1)

3 103 (17.3)

I.P.

100

100

105

(16.0)

(8.9)

(14.7)

6 107 (9.6) 104 (8.3)

12 118 (14.2)

18 102

(8.3.) (l:f6)

These values show a different effect of EtOH on GSH levels depending on the administration route. The differences, probably due to the first-pass effect, produce a drastic decrease (-42%) starting from 12 hours after i.p. administration.

EFFECTS OF COCAINE: ON VASCULAR ADP-ase Togna

G.*,

Togna

A.R.,

Benedetto

S.,

ACTIVITY

Caprino

L.

*Institute of Pharmacology, Catholic University, Rome IV Chair of Pharmacology, University of Rome "La Sapienza" Vessel wall ADP-ase plays an important role in degrading the circulating ADP thus contributing to the non-thrombogenic properties of endothelium (1). The present investigation was undertaken in order to verify the in effects of cocaine on the endothelium ADP-ase activity of rat aorvitro ADP-ase activity was measured by enzimatically evaluating the tic rings. residual ADP present in the medium (3 ml) at different times (5, 10, 15 mins) after incubation of rat aortic rings (50 mg wet weight)) with ADP (50 mcg) (2). Cocaine was added at concentrations of 50, 100, 250 mcg/ml. Compared to controls, cocaine induces a higher reduction of ADP level in the incubation medium, clearly showing an increased ADP-ase activity rate. Furthemore, the ADP-ase activity of "exhausted" (after repeated ADP exposure) aortic rings was found to be enhanced by addition of cocaine. In conclusion, cocaine appears to modify an important enzymatic activity of the vessel wall; however, on the basis of the present findings it is not easy to correlate the increased rate of ADP disappearance with the development of myocardial thrombosis demonstrated in cocaine users (3). 1)Liebermsn 27:447-56;

GE

et

3)KLonar

al.

Lancet

RR et al. Supported

1977;

2:330-2;

Circulation by

a

Grant

2)Caprino 1992;

of

HURST

L

et

X

1991

85:407-19. 40,

60

al.

Thromb.Res.1982;