RESUMEN
A fundamental feature of vocal communication is that animals produce vocalizations with different acoustic features in different behavioral contexts (contact calls, territorial calls, courtship calls, etc.). The midbrain periaqueductal gray (PAG) is a key region that regulates vocal production, and artificial activation of the PAG can elicit the production of multiple species-typical vocalization types.1,2,3,4,5,6,7,8,9 How PAG circuits are organized to regulate the production of different vocalization types remains unknown. On the one hand, studies have found that partial PAG lesions abolish the production of some vocalization types while leaving others intact,3,8,10,11 suggesting that different populations of PAG neurons might control the production of different vocalization types. On the other hand, electrophysiological recordings have revealed individual PAG neurons that increase their activity during the production of multiple vocalization types,12,13,14 suggesting that some PAG neurons may regulate the production of more than one vocalization type. To test whether a single population of midbrain neurons regulates the production of different vocalization types, we applied intersectional methods to selectively ablate a population of midbrain neurons important for the production of ultrasonic vocalizations (USVs) in mice. We find that, although ablation of these PAG-USV neurons blocks USV production in both males and females, these neurons are not required for the production of distress calls. Our findings suggest that distinct populations of midbrain neurons control the production of different vocalization types.
Asunto(s)
Ultrasonido , Vocalización Animal , Masculino , Femenino , Ratones , Animales , Vocalización Animal/fisiología , Neuronas/fisiología , Sustancia Gris Periacueductal/fisiología , CortejoRESUMEN
BACKGROUND: Recent studies have demonstrated that earlier time-of-day infusion of immune checkpoint inhibitors (ICIs) is associated with longer progression-free survival (PFS) and overall survival (OS) among patients with metastatic melanoma and non-small cell lung cancer. These data are in line with growing preclinical evidence that the adaptive immune response may be more effectively stimulated earlier in the day. We sought to determine the impact of time-of-day ICI infusions on outcomes among patients with metastatic renal cell carcinoma (mRCC). METHODS: The treatment records of all patients with stage IV RCC who began ICI therapy within a multicenter academic hospital system between 2015 and 2020 were reviewed. The associations between the proportion of ICI infusions administered prior to noon (denoting morning infusions) and PFS and OS were evaluated using univariate and multivariable Cox proportional hazards regression. RESULTS: In this study, 201 patients with mRCC (28% women) received ICIs and were followed over a median of 18 months (IQR 5-30). The median age at the time of ICI initiation was 63 years (IQR 56-70). 101 patients (50%) received ≥20% of their ICI infusions prior to noon (Group A) and 100 patients (50%) received <20% of infusions prior to noon (Group B). Across the two comparison groups, initial ICI agents consisted of nivolumab (58%), nivolumab plus ipilimumab (34%), and pembrolizumab (8%). On univariate analysis, patients in Group A had longer PFS and OS compared with those in Group B (PFS HR 0.67, 95% CI 0.48 to 0.94, Punivar=0.020; OS HR 0.57, 95% CI 0.34 to 0.95, Punivar=0.033). These significant findings persisted following multivariable adjustment for age, sex, performance status, International Metastatic RCC Database Consortium risk score, pretreatment lactate dehydrogenase, histology, and presence of bone, brain, and liver metastases (PFS HR 0.70, 95% CI 0.50 to 0.98, Pmultivar=0.040; OS HR 0.57, 95% CI 0.33 to 0.98, Pmultivar=0.043). CONCLUSIONS: Patients with mRCC may benefit from earlier time-of-day receipt of ICIs. Our findings are consistent with established mechanisms of chrono-immunology, as well as with preceding analogous studies in melanoma and lung cancer. Additional prospective randomized trials are warranted.