Inorganic phosphorus decrease after intravenous glucose tolerance test is associated with insulin resistance in dairy cows

Autor: Jože Starič, Marko Cincović, Branislava Belić, Nenad Stojanac, Aleksandar Potkonjak, Radojica Djokovic, Ognjen Stevančević, Bojan Toholj
Rok vydání: 2017
Předmět:
Zdroj: Veterinarski arhiv
Volume 87
Issue 4
ISSN: 1331-8055
0372-5480
DOI: 10.24099/vet.arhiv.160204
Popis: Inorganic phosphorus (Pi) concentration in blood decreases during an intravenous glucose tolerance test (IVGTT) due to the increase in the level of insulin and glucose. The objective of the present study was to determine the relationship between the intensity of Pi decrease with a dynamic change of insulin and glucose during IVGTT (AUC - total area under curve, AUC increment - area under curve from start of IVGTT to time of maximal response and glucose CR-clearance rate), as well as RQUICKI (Revised Quantitative Insulin Sensitivity Check Index) and RQUICKI-BHB (RQUICKI with beta hydroxybutyrate in formula) indexes of insulin resistance. The experiment included healthy and ketotic cows. Metabolic changes in ketotic cattle are similar to healthy cows in early lactation; ketosis represents impaired metabolic adaptation with higher insulin resistance. In both groups we found increases in insulin and glucose concentrations and Pi AUC during IVGTT, but these changes were less pronounced in the ketotic group. Ketotic cows showed a lower RQUICKI and RQUICKI-BHB index which indicates a higher level of insulin resistance. Pi AUC was in positive correlation with glucose response (glucose AUC), and this correlation is controlled with insulin response to glucose (insulin AUC). Pi AUC also showed a positive correlation with maximal glucose and insulin concentration during IVGTT, AUC and AUC increment for glucose and insulin, and glucose CR. These correlations were controlled by RQUICKI and RQUICKI-BHB indexes. The Pi decrease after the intravenous glucose tolerance test in dairy cows is associated with all aspects of insulin resistance, that include the insulin response to glucose (insulin AUC) and tissue response to insulin (RQUICKI and RQUICKI-BHB).
Koncentracija neorganskog fosfora (engl. inorganic phosphorus, Pi) u krvi opada tijekom intravenskog testa tolerancije na glukozu (engl. intravenous glucose tolerance test, IVGTT) zbog porasta koncentracije inzulina i glukoze. Cilj je ovog istraživanja bio da se utvrdi veza između opadanja vrijednosti Pi s dinamskim promjenama vrijednosti inzulina i glukoze tijekom IVGTT (AUC - ukupna površina ispod krivulje, AUC increment - površina ispod krivulje od početka IVGTT do trenutka kada se postiže maksimalni odgovor i CR-klirens glukoze), kao i vrijednostima indeksa inzulinske rezistencije RQUICKI (eng., Revised Quantitative Insulin Sensitivity Check Index) i RQUICKI-BHB (RQUICKI preinačen s vrijednošću beta-hidroksibutirata). U pokus su bile uključene zdrave i ketozne krave. Metaboličke promjene kod ketoznih krava slične su promjenama kod zdravih krava u ranoj laktaciji, s tim što ketoza nastaje kao znak loše metaboličke adaptacije s inzulinskom rezistencijom. U obje skupine ustanovljen je porast inzulina i glukoze i Pi AUC tijekom IVGTT, ali su ove promjene manje izražene kod ketoznih krava. Ketozne su krave imale nižu vrijednost RQUICKI i RQUICKI-BHB indeksa, što upućuje na veću razinu inzulinske rezistencije. Pi AUC je bio u pozitivnoj korelaciji s odgovorom glukoze (AUC glukoze), a ova je korelacija bila pod kontrolom odgovora inzulina na glukozu (AUC inzulina). Pi AUC pozitivno korelira s maksimalnom koncentracijom glukoze i inzulina postignutom tijekom IVGTT, AUC i AUC porasta za glukozu i inzulin i CR glukoze. Sve su navedene korelacije kontrolirane vrijednostima RQUICKI i RQUICKI-BHB indeksa. Opadanje Pi tijekom intravenskog testa tolerancije na glukozu kod mliječnih krava povezana je sa svim aspektima inzulinske rezistencije, što je odgovor inzulina na glukozu (AUC inzulina) i odgovor tkiva na inzulin (RQUICKI i RQUICKI-BHB)
Databáze: OpenAIRE
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