Response characteristics of two types of cold receptors on the antennae of the cockroach, Periplaneta americana L.

Self Cite

Most insects are equipped with specialized thermo- and hygroreceptors to locate a permissible range of ambient temperature and distant water sources, respectively. In the cockroach, Periplaneta americana, cold, moist, and dry receptor cells in the antennae send axons to particular sets of two or three glomeruli in the dorsocentral part of the antennal lobe (primary olfactory center), designated DC1-3 glomeruli. However, it is not known how thermo- and hygrosensory signals from these glomeruli are represented in higher-order centers, the protocerebrum, in any insect species. With the use of intracellular recording and staining techniques, we identified a new class of interneurons with dendrites almost exclusively in the DC1, DC2, or DC3 glomeruli and axons projecting to the protocerebrum in the cockroach. Remarkably, terminals of all these projection neurons (PNs) covered almost identical areas in the lateral protocerebrum (LP), although their termination areas outside the LP differed from neuron to neuron. The termination areas within the LP were distinct from, but close to, those of uniglomerular and macroglomerular PNs that transmitted signals concerning general odors and female sex pheromones, respectively. PNs originating from DC1, DC2, and DC3 glomeruli exhibited excitatory responses to cold, moist, and dry stimuli, respectively, probably due to excitatory synaptic input from cold, moist, and dry receptor cells, respectively, whereas their responses were often modulated by olfactory stimuli. These findings suggested that dorsocentral PNs participate in neural pathways that lead to behavioral responses to temperature or humidity changes.

Section: Physiologic Properties Of Hygro-and Thermosensory Pnsmentioning

confidence: 85%

Section: Neural Algorithm For Processing Thermo-and Hygrosensory Signalsmentioning

confidence: 88%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Projection neurons originating from thermo‐ and hygrosensory glomeruli in the antennal lobe of the cockroach

Nishino

Yamashita

Yamazaki

et al. 2002

Self Cite

“…The other is a double-walled and pored sensillum that also houses four neurons: one cold neuron and three olfactory neurons (C/O sensillum), according to Altner et al (1977). These cold receptor neurons respond differently to temperature change (Nishikawa et al, 1992). In the cold receptor neurons of the C/H sensilla, the steady-state activity is higher at lower constant temperature within 16-3loC, whereas, individually, the cold receptor neurons of the C/O sensilla have a broad activity maximum within 18-27°C.…”

Section: Rightmentioning

confidence: 99%

Central projections of the antennal cold receptor neurons and hygroreceptor neurons of the cockroach Periplaneta americana

Nishikawa

Yokohari

Ishibashi

1995

Self Cite

The central projections of the cold receptor axons were examined by filling two types of cold receptive sensilla with cobalt lysine--a cold and hygroreceptive (C/H) sensillum and a cold receptive and olfactory (C/O) sensillum--on the antennae of the cockroach, Periplaneta americana L. When the dye filled a single C/H sensillum, four axons were stained. Three of these axons terminate in the ipsilateral antennal lobe, while the other branches in the ipsilateral dorsal lobe. One of the branches passed through the tritocerebrum to terminate in the suboesophageal ganglion, while the other branches end in the lobe. When a single C/O sensillum is dye filled, all axons of the four receptor neurons terminate exclusively in the ipsilateral antennal lobe. One axon from the C/H sensillum and one axon from the C/O sensillum terminate in a particular glomerulus in the ventroposterior region of the antennal lobe. Each of these axons also has a tuft in separate glomeruli situated just dorsal to the glomerulus in which both axons terminate. This set of three glomeruli have indistinct boundaries and appear to form a complex of glomeruli similar to the macroglomerular complex of male moths. Assuming modality-specific convergence of antennal afferents, these axons appear to belong to the cold receptor neurons, and the set of glomeruli appear to function in cold reception. Two other neurons stained from C/H sensilla always terminate in the glom-eruli distinct from the set of glomeruli mentioned earlier. These neurons are assigned to the pair of hygroreceptor neurons, and their glomeruli are thought to function in hygroreception.

Sensillum‐specific, topographic projection patterns of olfactory receptor neurons in the antennal lobe of the cockroach Periplaneta americana

Watanabe

Haupt

Nishino

et al. 2012

Self Cite

In vertebrates and many invertebrates, olfactory signals detected by peripheral olfactory receptor neurons (ORNs) are conveyed to a primary olfactory center with glomerular organization in which odor-specific activity patterns are generated. In the cockroach, Periplaneta americana, ORNs in antennal olfactory sensilla project to 205 unambiguously identifiable antennal lobe (AL) glomeruli that are classified into 10 glomerular clusters (T1-T10 glomeruli) innervated by distinct sensory tracts. In this study we employed single sensillum staining techniques and investigated the topographic projection patterns of individual ORNs to elucidate the relationship between sensillum types and glomerular organization in the AL. Axons of almost all ORNs projected to individual glomeruli. Axons of ORNs in perforated basiconic sensilla selectively innervated the anterodorsal T1-T4 glomeruli, whereas those in trichoid and grooved basiconic sensilla innervated the posteroventral T5-T9 glomeruli. About 90% of stained ORNs in trichoid sensilla sent axons to the T5 glomeruli and more than 90% of ORNs in grooved basiconic sensilla innervated the T6, T8, and T9 glomeruli. The T5 and T9 glomeruli exclusively receive sensory inputs from the trichoid and grooved basiconic sensilla, respectively. All investigated glomeruli received convergent input from a single type of sensillum except F11 glomerulus in the T6 glomeruli, which was innervated from both trichoid and grooved basiconic sensilla. These results suggest that ORNs in distinct sensillum types project to glomeruli in distinct glomerular clusters. Since ORNs in distinct sensillum types are each tuned to distinct subsets of odorant molecules, the AL is functionally compartmentalized into groups of glomeruli.