Author/Editor		Pangršič, Tina
Title		Analiza faz povišane porabe kisika v očesu muhe (Calliphora erythrocephala - chalky)
Translated title		Analysis of the phases of increased oxygen consumption in the eye of the blowfly Calliphora erythrocephala - chalky during illumination
Type		monografija
Place		Ljubljana
Publisher		Biotehniška fakulteta, Oddelek za biologijo
Publication year		2001
Volume		str. 54
Language		slo
Abstract		Insect eye has high energy demands that are met by energy ofATP molecules mostly produced in the process of cellular respiration. The process must be supplied with oxygen to drive the respiratory chain. We can easily influence the rate of energy and therefore oxygen consumption by light stimulation. The consumption of oxygen can be measured by a magnetic diver balance which allows precise volumetric measurements. The increased light-induced consumption shows two kinetic phases fitted by a double exponential function, as previously described. We analysed them in the eye of the blowfly Calliphora erythrocephala- chalky by changing temporal and intensity stimulation parameters. The dependency between stimuli duration and increase in oxygen consumption was fitted by a double Hill sigmoid at bright or a single at dimmer illumination with parameters corresponding to the second sigmoid. The assumption of the model, which can not yet be proven, is that the function is the sum of two sigmoids. The analysis of the peaks of consumption at short illuminations shows large discrepancies between peaks and consumption levels at same times during longer illuminations. Two characteristic discrepancy peaks appear in the ranges of the kink in a double sigmoid in the first and the break of double exponential curve in the second case. Further on, those times also coincide with the time of receptor potential adaptation and the peak of respiratory chain elements oxidation. Therefore, we assume that the single response curve shows the time course of mitochondrial activation, while the observed kink in the sigmoid curve is more likely due to cellular adaptation.
Descriptors		EYE OXYGEN CONSUMPTION PHOTIC STIMULATION DIPTERA