Portal de Periódicos da CAPES

Effects of β-adrenergic blockade or stimulation on net rate of hydrothorax absorption

1994; Elsevier BV; Volume: 97; Issue: 3 Linguagem: Inglês

10.1016/0034-5687(94)90070-1

1872-7611

Luciano Zocchi, Emilio Agostoni,

Inhalation and Respiratory Drug Delivery

We determined in anesthetised rabbits the net rate of liquid absorption (NRLA) from Ringer or 1% albumin-Ringer hydrothoraces with the β-blocker propranolol (or nadolol) or the β-agonist terbutaline. The β-blocker raduced NRLA by 38% in 2 ml Ringer hydrothoraces, and did not change it in 2 ml albumin-Ringer hydrothoraces; hence, with β-blocker NRLA became similar in both kinds of hydrothorax (0.31 ± 0.02 ml/h). Terbutaline decreased NRLA by 25% in 2 ml Ringer hydrothoraces, and increased it by 29% in 2 ml albumin-Ringer hydrothoraces; hence, with terbutaline NRLA became similar in both kinds of hydrothorax (0.40 ± 0.02 ml/h), and 25% higher than with β-blocker. Because β-adrenoreceptor activity inhibits lymphatic smooth muscles and may increase Na+ transport in epithelia, these results suggest that: (1) pleural mesothelium is provided with β-receptors, which increase Na+ transport and seem activated by protein dilution, (2) β-receptors of the pleural lymphatics are essentially silent with an without protein dilution, (3) the lumphatic drainage produced by smooth muscle activity is smaller than the increase in solute-couple liquid absorption caused by mesothelium β-receptros.