Background odour induces adaptation and sensitization of olfactory receptors in the antennae of houseflies

Abstract

Abstract. The presence of background odour was found to have a small but significant effect on the sensitivity of the antennal olfactory system of houseflies, Musca domestica Linnaeus (Diptera: Muscidae), to new pulses of odour. We show that cross-adaptation and cross-sensitization between a background odour of (AE)-1-octen-3-ol and pulses of (AE)-1-octen-3-ol, 2-pentanone and R-( )-limonene can occur, confirming that olfactory receptor cells are sensitive to different odours. Background odour can increase the responses to low concentration odour pulses and decrease the responses to higher concentration odour pulses. It is suggested that background odour has a larger effect on olfactory receptor cells that respond with a tonic increase of spike frequency, giving information about the level of odour concentration, i.e. the`static' environment. Cells that respond in a phasic way only provide information on the dynamics of the olfactory environment.

Impact of elevated CO2 background levels on the host-seeking behaviour of Aedes aegypti

“…The response to CO 2 , as a function of the stimulus (spikes s −1 ppm −1 ), was significantly reduced when the background level increased. Similar observations have been made for CO 2 detection in the moth C. cactorum (Stange and Wong, 1993;Stange, 1997), for 1-octen-3-ol detection in the fly Musca domestica (Kelling et al, 2002), and for pheromone detection in a wide variety of moths (Willis and Baker, 1984;Mafra-Neto and Baker, 1996;Evenden et al, 2000). The compressive non-linearity suggests that insects experiencing elevated background concentrations of stimuli either are unable to perceive the stimulus or are habituated, which consequently affects their behavioural performance.…”

Olfactory coding in Drosophila larvae investigated by cross-adaptation

“…Increases in sensitivity following cross-adaptation have been observed in electrophysiological studies on lobster receptor cells (Borroni and Atema, 1989), rat trigeminal nerve (Farley and Silver, 1992) and the housefly antenna (Kelling et al, 2002). However, none of the data presented in Figs·4 and 5 fit this profile.…”

“…Paradoxically, one of the effects of olfactory adaptation to a given odour can be to enable the organism to detect small changes in the levels of other substances (Kelling et al, 2002;Fain, 2003). This effect, coupled with the fact that in the natural world animals are often in the presence of continuous background odours (e.g.…”

“…This approach, known as cross-adaptation, has been employed in studies of chemosensation in a range of organisms, including bacteria (Gestwicki and Kiessling, 2002), lobsters (Daniel et al, 1994), mice (Kelliher et al, 2003), frogs (Takeuchi et al, 2003), houseflies (Kelling et al, 2002), C. elegans (Colbert and Bargmann, 1995), Manduca sexta (Dolzer et al, 2003) and Drosophila adults (de Bruyne et al, 1999) and larvae (Cobb and Domain, 2000).…”

The Relevance of Background Odor in Resource Location by Insects: A Behavioral Approach

“…Usually, before resource location, the insect is exposed to habitat odor for some time. This previous exposure to habitat odor may induce habituation or sensitization (Kaissling 1986, 1996, Masson and Mustaparta 1990, Smith and Getz 1994, Kelling et al 2002, thus adding a further dimension (time) to odor quality and quantity when considering discrimination of RIO and background odor. The space between odor sources is also known to play a role for discrimination of different odor blends (Bruce et al 2005).…”