A MTA Tihanyi Biológiai Kutatóintézetének Évkönyve 34. (1967)

1. ÁLLATTAN - Lábos Elemér: Contributions to the mechanism of activating light cation effect on glochidia = Adatok alkáli fém és földfém ionok aktiváló hatásának mechanizmusához Anodonta lárván

CONTRIBUTIONS TO THE MECHANISM OF ACTIVATING LIGHT CATION EFFECT ON GLOCHIDIA ELEMÉR LÁBOS Biological Research Institute of the Hungarian Academy of Sciences, Tihany, Hungary Received: 24th February, 1967 Adductor response of mussel larva (Anodonta-glochidium) was observed in the presence of alkali and alkaline earth metal ions. Previously, we (Lábos and Salánki 1963) reported about the K+ ion evoking an extremely long lasting rhythmic activity and have shown some features of Na+ , Li+, Cs + , Rb+, Ca2 + and Mg2+-e effects, too. Furthermore, the difference between K+- and tryptamine-responses in the susceptibility to cholinotropic phar­­macons and SH-inhibitors also was pointed out (Lábos and his co-workers 1964a, 1964b). In the present paper we attempt to answer some of the problems of К +­­effect from a pharmacological aspect. Mainly the tonic response of larvae was examined. We focussed our attention on the following questions: 1. activity-sequence of ions and its changes, 2. ion-antagonisms and synergisms, 3. metabolic inhibitors and ion-effect, 4. heavy water isotope-effect. Method and materials In groups of mussel-larvae rhythmic contractions were counted and the number of closed glochidia was noted by a method described previously (Lábos and Salánki 1963). In general, observations were compared originating from experiments with at least 100—100 glochidia. As different measures of effects the number of contractions accomplished by 100 larvae in 1 or 10 minutes (a/min, Ea), the ratio of closed glochidia after the application of the agents with t minutes (ct) were used. The applied substances were: KCl, NaCl, CaCl2, MgCl2, RbCl (BDH), CsCl (Fluka), LiCl (BDH), SrCl2 (Merck), ouabain (Ph. Hg. IV.), 2,4-dinitro­­phenol, (2,4-DNP; Reanal), 2,4-DNP-hydrazine (Reanal; 2,4-DNPH), NaF, KCN, NaNg (BDH), digitonin (BDH), cetylpyridine-bromide (EGYT) papaverin-HCl (Chinoin), ethanol, parachloromercuri-benzoic acid (PCMB; Light), N-ethyl-maleimide (BDH; NEM), D20, NaSCN, veratrine-sulphate (Merck), histamine-diHCl (Light), guanidine-HC03 (Fluka), tryptamine-HCl (Fluka), serotonin-creatinine-sulphate (Fluka; 5-HT), dopamine-HCl (Fluka), d-tubocurarine-HCl (d-TC; Schuchardt), tetramethylammoniumiodide (BDH; ANNAL. BIOL. TIHANY 34 3—24 HUNGÁRIA 1967 l*

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