Utjecaj načina ekspozicije na akutnu toksičnost inhibitora kolinesteraze

The acute toxicities of some cholinesterase inhibitor compounds have been determined by the oral, intraperitoneal, subcutaneous, intravenous and intracerebral routes of injection in female mice. The coupounds studied were monocrotophos, dicrotophos, mevinphos, crotoxyphos, dichlorvos, chlorfenvinphos, paraoxon, parathion, neostigmine and eserine. Compounds which are rapidly degraded by the liver are less toxic following oral and intraperitoneal (hepatic routes) injection than they are by subcutaneous and intravenous (peripheral routes) injection. Parathion, which is activated by the liver, tends to be more toxic following administration by the intraperitoneal (hepatic) route. Intracerebral injection by-passes the blood-brain barrier, and the compounds show, with one or two exceptions, a similar order of toxicity by this route of administration compared with the other routes of injection.Određena je akutna toksičnost nekih inhibitora kolinesteraze za ženke miševa nakon oralne, intraperitonealne, supkutane, intravenozne i intracerebralne aplikacije. Proučavani spojevi bili su: monokrotofos, dikrotofos, mevinfos, krotoksifos, diklorvos, klorfenvinfos, paraokson, paration. neostigmin i ezerin. Spojevi što ih jetra brzo razgrađuje manje su toksični nakon oralne i intraperitonealne (hepatalni putevi) nego nakon supkutane i intravenozne aplikacije (periferni putevi). Paration, koji jetra aktivira, postaje toksičniji nakon intraperitonealne aplikacije (hepatalni put). Intracerebralna aplikacija mimoilazi hematoencefalnu barijeru i, osim jedne ili dvije iznimke, ovi spojevi pokazuju sličnu toksičnost nakon ovog puta aplikacije u usporedbi s drugim putevima

Utjecaj načina ekspozicije na akutnu toksičnost inhibitora kolinesteraze

The acute toxicities of some cholinesterase inhibitor compounds have been determined by the oral, intraperitoneal, subcutaneous, intravenous and intracerebral routes of injection in female mice. The coupounds studied were monocrotophos, dicrotophos, mevinphos, crotoxyphos, dichlorvos, chlorfenvinphos, paraoxon, parathion, neostigmine and eserine. Compounds which are rapidly degraded by the liver are less toxic following oral and intraperitoneal (hepatic routes) injection than they are by subcutaneous and intravenous (peripheral routes) injection. Parathion, which is activated by the liver, tends to be more toxic following administration by the intraperitoneal (hepatic) route. Intracerebral injection by-passes the blood-brain barrier, and the compounds show, with one or two exceptions, a similar order of toxicity by this route of administration compared with the other routes of injection.Određena je akutna toksičnost nekih inhibitora kolinesteraze za ženke miševa nakon oralne, intraperitonealne, supkutane, intravenozne i intracerebralne aplikacije. Proučavani spojevi bili su: monokrotofos, dikrotofos, mevinfos, krotoksifos, diklorvos, klorfenvinfos, paraokson, paration. neostigmin i ezerin. Spojevi što ih jetra brzo razgrađuje manje su toksični nakon oralne i intraperitonealne (hepatalni putevi) nego nakon supkutane i intravenozne aplikacije (periferni putevi). Paration, koji jetra aktivira, postaje toksičniji nakon intraperitonealne aplikacije (hepatalni put). Intracerebralna aplikacija mimoilazi hematoencefalnu barijeru i, osim jedne ili dvije iznimke, ovi spojevi pokazuju sličnu toksičnost nakon ovog puta aplikacije u usporedbi s drugim putevima

Paraoxonase activity in sera from Piaractus mesopotamicus Holmberg (Characidae) and Hypostomus punctatus Valenciennes (Siluridae)

A paraoxonase activity present in serum of two Brazilian fish species was consistently assayed at pH 8.5 using 7.5 mM paraoxon final concentration. The paraoxonase activity was more activated by 0.5 M NaCl in serum of Piaractus mesopotanricus Holmberg, 1887 (pacu) than in serum of Hypostomus punctatus Valenciennes, 1840 (cascudo). Apparent values of K M were 3.3 x 10-3 M for cascudo and pacu paraoxonase activity in the presence of 0.5 M NaCl. Apparent maximum velocity values calculated in the presence of 0.5 M NaCl were 6.1 and 6.5 nmole/min/mL of serum for cascudo and pacu, respectively. Vmax/K M ratio values of determinations in the presence and absence of 0.5 M NaCl showed that NaCl had a more evident effect on increasing the affinity of serum paraoxonase for paraoxon in pacu serum. Young specimens of pacu showed a marked decreased paraoxonase serum activity when kept in tanks treated with 0.25 ppm methyl-parathion