The GAIA theory: from Lovelock to Margulis. From a homeostatic to a cognitive autopoietic worldview

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Role of nitric oxide-dependent and independent mechanisms in peristalsis and accommodation in the rabbit distal

ABSTRAC

Monitoraggio di fauna ittica nelle zone interessate da barriere artificiali sommerse nelle acque costiere adriatiche della Regione Abruzzo

Le Province di Teramo e Pescara hanno installato tre barriere artificiali sommerse costituite da moduli in calcestruzzo e da massi naturali nelle acque costiere della regione Abruzzo per il ripopolamento della fauna ittica e per impedire la pesca a strascico illegale, utilizzando specifici finanziamenti europei. Le Province hanno affidato all’Istituto G. Caporale l’incarico di monitorare l’evoluzione delle popolazioni nectobentoniche mediante 3 campionamenti annuali in ciascuna barriera artificiale. Questo lavoro riporta i risultati dello studio condotto dal 2005 al 2007, ottenuti comparando le catture effettuate nelle aree interessate dalle barriere con quelle dei siti di controllo attraverso l’uso di alcuni indici di diversità. Le aree interessate da barriere artificiali mostrano una maggiore diversità e ricchezza di specie rispetto alle aree di controllo. Pertanto le barriere artificiali possono contribuire sia a risolvere i problemi legati allo scarso reddito della pesca artigianale e all’eccessivo sfruttamento delle risorse alieutiche, sia all’avvio di quei processi di diversificazione degli habitat che facilitano l’incremento della diversità biologica

Monitoring of ichthyic fauna in artificial reefs along the Adriatic coast of the Abruzzi Region of Italy

With the support of European Community funds, three submerged artificial reefs composed of concrete cubes, bell-shaped modules and natural rocks were deployed along the Adriatic coast of the Abruzzi Region to increase the fish population and to prevent illegal trawling. The Provincial governments of Teramo and Pescara requested the Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise ‘G. Caporale’ to monitor nectobenthic populations. Three sampling operations were conducted each year for each artificial reef. The authors present the results of a study conducted between 2005 and 2007, comparing the catches from the artificial reefs with those from the control sites using several diversity indexes. Artificial reef areas revealed greater species diversity and richness than the control sites. This study demonstrates the value of artificial reefs in response to the problem of low income, non-commercial fisheries as well as to the issue of over-exploitation of halieutic resources. In addition, the authors suggest that artificial reefs may be capable of activating habitat diversification processes that will increase biodiversity

Peristalsis regulation by tachykinin NK1 receptors in the rabbit isolated distal colon

In the gastrointestinal tract, tachykinin NK1 receptors are widely distributed in a number of neuronal and nonneuronal cells involved in the control of gut motor activity. In particular, in the rabbit isolated distal colon, which is a suitable model system to investigate the contribution of tachykinins as noncholinergic excitatory transmitters, the influence of NK1 receptors in the regulation of peristalsis is not known. The selective NK1-receptor antagonists SR-140333 (0.3 and 1 nM) and MEN-10930 (0.3-10 nM) significantly enhanced the velocity of rabbit colonic propulsion to submaximal stimulation. The prokinetic effect of SR-140333 was prevented by N-omega-nitro-L-arginine (L-NNA), a nitric oxide synthase inhibitor, indicating that NK1 receptors located on nitrergic innervation exert a functional inhibitory restraint on the circular muscle and probably on descending excitatory and inhibitory pathways during propulsion. Conversely, the selective NK1-receptor agonist septide (3-10 nM) significantly inhibited colonic propulsion. In the presence of L-NNA, the inhibitory effect of septide was reverted into a prokinetic effect, which is probably mediated by the activation of postjunctional excitatory NK1 receptors